Self-organized and self-managed ad hoc communications network

ABSTRACT

A self-organized and self-managed ad hoc network operates without the intervention of arbitration, collision detectors, hubs, master controllers, switches, or routers. The network may include both fixed and/or mobile stations. A self-organized and self-managed order of transmission sequence is automatically determined by the stations in the network, and then each station transmits in the order defined by that sequence. Stations can join in, or drop out of, the network at any time with little to no disruption of the network, and the transmission sequence is automatically updated to accommodate a joinder or removal.

FIELD OF INVENTION

The present invention generally relates to networks and, moreparticularly, to self-organized, self-managed and efficient ad hoccommunications networks, which provide for a number of opportunities foreach station to transmit over a complete Authority To Transmit Sequencecycle, near-optimization of the network bandwidth using the Authority ToTransmit Sequence, and/or adding and dropping stations withoutdisrupting the network.

Portions of the disclosure herein contain material that is subjectprotected by copyright. The copyright owner has no objection to thefacsimile reproduction by anyone of the patent document or the patentdisclosure as it appears in the Patent and Trademark Office file and/orrecords, but otherwise reserves all rights in such copyrights.

ATTS™, BSTTS™, IDM™, and IDMA™ are trademarks and/or service marks ofAbidaNet LLC.

BACKGROUND OF THE INVENTION

There is an ever-increasing need to automatically organize and manage adhoc communications networks and obtain more bandwidth and/or betterutilization of existing bandwidth for those networks, and for higherthroughput. Even a basic discussion, however, of the numerous types ofcommunications networks and protocols would occupy pages of material.Therefore, in order not to burden the knowledgeable reader with adiscussion of the prior art, and in order to allow the reader to focuson the present invention, the prior art communications networks are notdiscussed in this background. Suffice it to say that the various priorart communications networks suffer from one or more problems, includingfailure to provide equal opportunity to transmit for all stations,failure to realistically provide for near-optimization of thetransmission authority sequence, and failure to provide for adding anddropping stations without disrupting the network. For the interestedreader, a detailed description of the operation and deficiencies ofknown prior art networks is provided in Appendix A, which is attachedhereto, all of which is incorporated herein by reference as if fully setforth at this point in this Background.

SUMMARY

A method of operating a network is described. The network has aplurality of stations, each station being capable of transmitting andreceiving. The network is preferably operated by defining anAuthorization To Transmit Sequence (ATTS) which specifies the order inwhich the stations may transmit, the ATTS listing a first station, atleast one intermediate station, and a last station, transmitting amessage from the first station, transmitting a message from each of theintermediate stations in their order of listing, transmitting a messagefrom the last station, reversing the order of the ATTS, transmittinganother message from the last station, transmitting another message fromeach of the intermediate stations in their reverse order of listing,transmitting another message from the first station, and then repeatingthe process beginning with transmitting a message from the firststation. A reverse ATTS is preferably used which specifies the order inwhich the stations may transmit and which order is reverse to that ofthe ATTS.

Another method of operating a network is also described. The network hasa plurality of stations, each station being capable of transmitting andreceiving. The network is preferably operated by obtaining anAuthorization To Transmit Sequence (ATTS) which specifies the order inwhich the stations may transmit, the ATTS listing a first station, atleast one intermediate station, and a last station, defining a reverseATTS based upon the ATTS, the order in which the stations may transmitbeing reverse to the order of the ATTS, receiving messages, inspectingeach message to determine if it was from a predecessor station in theATTS or in the reverse ATTS, and if the message was from a predecessorstation then, once that message is complete, transmitting a message.

In this method an option is to estimate the time at which a message fromthe predecessor station should be received and, if that estimated timehas passed and a message has not been received from the predecessorstation, then transmitting a message.

In this method another option is to estimate the time at which a messagefrom the predecessor station should be received and, if that estimatedtime has passed and a message has not been received from the predecessorstation, then removing that predecessor station from the ATTS and thereverse ATTS.

In this method still another option is to estimate the time at which amessage from the predecessor station should be received and, if thatestimated time has passed and a message has not been received from thepredecessor station, then transmitting a message and removing thatpredecessor station from the ATTS and the reverse ATTS.

Another method of operating a network is also described. The network hasa plurality of stations, each station being capable of transmitting andreceiving. The network is preferably operated by obtaining anAuthorization To Transmit Sequence (ATTS) which specifies the order inwhich the stations may transmit, the ATTS listing a first station, atleast one intermediate station, and a last station, at a predeterminedtime, sending a pause message to invite a new station to join thenetwork, if a reply message is received then sending a station identityand the ATTS to the new station, receiving a revised ATTS from the newstation, the revised ATTS listing the new station, and transmitting amessage in accordance with the revised ATTS.

In this method an option is to inspect each message to determine if itwas from a predecessor station in the revised ATTS and, if the messagewas from a predecessor station, then, once that message is complete,beginning transmission of a message.

A method of operating a station wishing to join a network is alsodescribed, the network comprising a plurality of stations, each stationbeing capable of transmitting and receiving. The station is preferablyoperated by listening on the network for a pause message inviting newstations to join the network, sending a reply to the pause message,receiving an Authorization To Transmit Sequence (ATTS) which specifiesthe order in which the stations may transmit, the ATTS listing a firststation, at least one intermediate station, and a last station,determining propagation times between the joining station and at leastsome of the stations listed in the ATTS, determining a position in theATTS where the joining station should be placed, defining a revised ATTSlisting the joining station in that position, receiving a messageauthorizing the joining station to transmit, transmitting a message, themessage including the revised ATTS, and transmitting further messages inaccordance with the revised ATTS.

In this method an option is to determine the position so as to maintainnetwork efficiency.

A method of operating a station wishing to join a network is alsodescribed, the network comprising a plurality of stations, each stationbeing capable of transmitting and receiving. The station is preferablyoperated by listening on the network for a pause message inviting newstations to join the network, sending a reply to the pause message,receiving a designation of a Parent Station in a cluster and at leastpart of an Authorization To Transmit Sequence (ATTS) which specifies theorder in which the stations may transmit, the ATTS listing a firststation, at least one intermediate station, and a last station, the atleast part including stations in the cluster, determining propagationtimes between the joining station and at least some of the stations inthat cluster which are listed in the at least part of the ATTS,determining a position in the at least part of the ATTS where thejoining station should be placed with respect to the stations in thatcluster so as to maintain network efficiency, defining a revised atleast part of the ATTS listing the joining station in that position,receiving a message authorizing the joining station to transmit,transmitting a message, the message including the revised at least partof the ATTS, and transmitting further messages in accordance with the atleast part of the revised ATTS.

In this method an option is to receive a local ATTS, the local ATTSbeing included within the ATTS.

In this method another option is to determine a plurality of networkpropagation times, each network propagation time being for a differentordering of transmissions for the at least part of the ATTS andincluding the joining station, and being based upon propagation timesbetween the joining station and at least some of the stations in thatcluster which are listed in the at least part of the ATTS, determine theminimum propagation time of the plurality of network propagation times,and provide the ordering of transmissions which resulted in the minimumpropagation time as a revised at least part of the ATTS.

A network has a plurality of stations, each station being capable oftransmitting and receiving. Each station preferably has a transmitter totransmit messages, a receiver to receive messages, a controllerfunctionally connected to the transmitter to control the transmitter,functionally connected to the receiver to process messages received bythe receiver, and also has a memory to store and retrieve anAuthorization To Transmit Sequence (ATTS) which specifies an order inwhich the stations may transmit, the ATTS listing a first station of theplurality of stations, at least one intermediate station of theplurality of stations, and a last station of the plurality of stations,the controller being responsive to the ATTS and to a reverse ATTS, thecontroller of the first station causes the transmitter of the firststation to transmit a first message if the ATTS is in effect, and thecontroller inspects a received message and causes the transmitter of thefirst station to transmit a second message if the reverse ATTS is ineffect and the received message was transmitted by an immediatelypreceding station in the reverse ATTS, the controller of eachintermediate station inspects a received message and causes thetransmitter of the intermediate station to transmit a message if theATTS is in effect and the received message was transmitted by animmediately preceding station in the ATTS, and causes the transmitter ofthe intermediate station to transmit a message if the reverse ATTS is ineffect and the received message was transmitted by an immediatelypreceding station in the reverse ATTS, and the controller of the laststation inspects a received message and causes the transmitter of thelast station to transmit a first message if the ATTS is in effect andthe received message was transmitted by an immediately preceding stationin the ATTS, and causes the transmitter of the last station to transmita second message if the reverse ATTS is in effect and the receivedmessage was transmitted by an immediately preceding station in thereverse ATTS, whereby a sequence of transmission of the stations is forthe first station listed in the ATTS to transmit, each intermediatestation to transmit in its order of listing in the ATTS, the laststation listed in the ATTS to transmit, the last station to transmitagain, each intermediate station to transmit in its order of listing inthe reverse ATTS, and the first station to transmit again; and wherebythe sequence of transmissions is executed at least one more time.

In this network, one option is for a controller to implement a reverseATTS by reversing the order in the ATTS.

In this network, another option is for a controller to also cause thetransmitter to transmit a message if the ATTS is in effect and a messagewas not timely received from an immediately preceding station in theATTS, or to cause the transmitter to transmit a message if the reverseATTS is in effect and a message was timely received from an immediatelypreceding station in the reverse ATTS.

In this network, another option is for a station to have a stationinterface, and the controller to be in the station interface.

A station for use with a network having a plurality of stations is alsodescribed, each station being capable of transmitting and receiving. Astation has a transmitter to transmit messages, a receiver to receivemessages, and a controller functionally connected to the transmitter tocontrol the transmitter, functionally connected to the receiver toprocess messages received by the receiver, and having a memory to storeand retrieve an Authorization To Transmit Sequence (ATTS) whichspecifies when the station may transmit with respect to other stationslisted in the ATTS, the ATTS listing a plurality of stations, theplurality of stations having a first station, at least one intermediatestation, and a last station, the controller being responsive to the ATTSand to a reverse ATTS to cause the transmitter to transmit, thecontroller inspecting a received message and causing the transmitter totransmit a message if the ATTS is in effect and the received message wastransmitted by an immediately preceding station in the ATTS, or causingthe transmitter to transmit a message if the reverse ATTS is in effectand the received message was transmitted by an immediately precedingstation in the reverse ATTS.

Optionally, a controller may implement a reverse ATTS by reversing theorder in the ATTS.

Also optionally, the controller may also cause the transmitter totransmit a message if the ATTS is in effect and a message was not timelyreceived from an immediately preceding station in the ATTS, or cause thetransmitter to transmit a message if the reverse ATTS is in effect and amessage was timely received from an immediately preceding station in thereverse ATTS.

Also optionally, if a station is the first station in the ATTS, thecontroller of the first station causes the transmitter of the firststation to transmit a first message if the ATTS is in effect, and thecontroller inspects a received message and causes the transmitter of thefirst station to transmit a second message if the reverse ATTS is ineffect and the received message was transmitted by an immediatelypreceding station in the reverse ATTS.

Also optionally, if a station is the last station in the ATTS, thecontroller of the last station inspects a received message and causesthe transmitter of the last station to transmit a first message if theATTS is in effect and the received message was transmitted by animmediately preceding station in the ATTS, and causes the transmitter ofthe last station to transmit a second message if the reverse ATTS is ineffect and the received message was transmitted by an immediatelypreceding station in the reverse ATTS.

Also optionally, a station may have a station interface, and thecontroller may be in the station interface.

The present invention provides for networks that is are self-organizing.

The present invention provides for networks that is are self-managed.

The present invention provides for a network in which each device has anumber of opportunities, including, but not limited to, an equal numberof opportunities to transmit over a complete Authority To TransmitSequence cycle.

The present invention provides for a network in which collisiondetection and avoidance schemes are not required.

The present invention provides for a network in which stations can jointhe network or drop out of the network without disruption networkoperations.

These different benefits provided by the present invention may be usedindividually or in combination with one, some or even all of the otherbenefits.

Further features and advantages of the invention will be apparent fromthe Drawing and the description below.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 illustrates a planar cross-section projection of the behavior ofa five Station BSTTS network transmitting in 3-dimensional free space.

FIG. 2 illustrates the distribution of broadcast energy along a radialtransmission cross-section of the planar cross-section projection inFIG. 1.

FIG. 3 illustrates a typical BSTTS message as it might appear on atransmission media.

FIG. 4A is a network showing two stations connected via StationInterfaces.

FIGS. 4B and 4C show network events for ATTS IDM message Cycles asdetected and processed at different Station Interfaces.

FIG. 5A illustrates an exemplary branched network.

FIGS. 5B-5G illustrate the operation of an MPT ATTS as transmitted,received and processed by Station Interfaces and also illustrate thetiming of a normal IDM Message Cycle across the network.

FIG. 6 illustrates some examples of transmission media.

FIGS. 7A and 7B illustrate propagation times and propagation timeequalities used in connection with the descriptions concerning thenetwork.

FIG. 8 is an illustration of a larger BSTTS network with a plurality ofconnected fixed and/or mobile stations and one station requesting tojoin.

FIG. 9 is an exemplary state transition diagram illustrating the variousstates of a Station Interface.

FIGS. 10-12 illustrate the message sequence diagrams for startup andjoinder conditions.

FIGS. 13A and 13B are block diagrams illustrating the functionalelements of an exemplary Station Interface.

DETAILED DESCRIPTION

Turn now to the several Figures of the Drawing in which reference ismade in detail to various embodiments of the present invention. Thepreferred environment of the present invention is a collection of fixedand/or mobile stations forming one or more transmission networks. Anyavailable and appropriate transmission media, singularly or incombination, without regard to media boundaries, may be used. Somenon-limiting examples of transmission media, which may be used, areshown in FIG. 6.

For convenience of discussion, certain abbreviations are used herein, asshown in Table 1 below.

TABLE 1 ABBREVIATIONS ABBREVIATION MEANING ATTS Authority To TransmitSequence BOS Beginning of Sequence BSTTS Branched Space-TimeTransmission System(s) CD Collision Detection CDM Code DivisionMultiplexing CDMA Code Division Multiple Access CSMA Carrier SenseMultiple Access EBM Ending Bus Master EOS End of Sequence FDM FrequencyDivision Multiplexing FDMA Frequency Division Multiple Access FOBWDMFiber Optic Bus Wavelength Division Multiplexing ID IDentification IDMInformation Division Management; IDMA Information Division MultipleAccess IEEE Institute of Electrical and Electronics Engineers LLCLimited Liability Company MIL MILitary (United States of America) MPTMinimum Propagation Time MST Minimal Spanning Tree OFDM OrthogonalFrequency Division Multiplexing OFDMA Orthogonal Frequency DivisionMultiple Access PT Propagation Time SBM Starting Bus Master STD STandarDTDM Time Division Multiplexing TDMA Time Division Multiple Access TSPTraveling Salesperson Problem US United States

The BSTTS station interface methods and devices described hereinconstruct, optimize, and self-manage the flow of information between thestations and transmission media, including, but is not limited to, theorganization, control, and optimization of the flow of informationthrough communications media. Hereinafter a BSTTS Station Interface isreferred to as “Station Interface”.

A BSTTS network consists of one or more stations, including theirStation Interfaces, connected in one or more network topologies, andinterfaced to any appropriate and available transmission media.Preferably, each active Station Interface holds an identical copy of anordered set of transmitter identities, the ATTS, which specifies theprogression in which Station Interfaces are permitted to transmit.Station transmitters do not transmit at times and/or at frequenciesother than those times and those frequencies specified by the ATTS,thereby eliminating collisions and the need for arbitration.

Among other things, the ATTS provides order and prevents collisions whena plurality of Station Interfaces use the same communications technologyand might otherwise interfere with each other's communications.Different ATTS may exist for different media. For example, there may beone ATTS for wired communications, another ATTS for low frequencycommunications, another ATTS for high frequency communications, stillanother ATTS for acoustic communications, etc. Further, a StationInterface may operate under more than one ATTS. For example, the StationInterface may use one ATTS for performing low frequency communications,another ATTS for performing high frequency communications, and stillanother ATTS for performing acoustic communications.

A beginning station on the ATTS, which is not necessarily the firststation of the ATTS ordered set, initiates a message transmission cycleby sending its data message. The remaining stations then transmit theirmessages in the order specified by the ATTS. Preferably, the beginningStation Interface of the ATTS awaits the arrival of the data from thelast Station Interface defined by the ATTS. When its turn to transmitarrives the last station could, for example, send its message and, whenthat message reached the beginning station, the process would beginagain starting with the first station. In the preferred embodiment,however, rather than wasting the bandwidth waiting for that message totravel from the last station back to the beginning station, a second,reverse ATTS message set is initiated. Thus, after transmitting itsmessage, which can include a payload, for the forward ATTS sequence, thelast Station Interface immediately reverses the ATTS and sends a secondmessage, which can also carry a payload. When the authority to transmit,as specified by the reverse ATTS, reaches the beginning station, thetransmit ATTS is again reversed. One of these transmission sequences inwhich each station has two opportunities to transmit is considered to bean “IDM Message Cycle.” If a Station Interface does not have a datapacket ready to send when it is that Station Interface's turn totransmit, then that Station Interface transmits a status message insteadof payload data. This maintains the ATTS integrity and also allows thatStation Interface to report its current statistics and/or to indicateits continued presence on the network.

During normal operation, data traffic is maintained entirely by the flowof data or status information between Station Interfaces in the ATTSprescribed order, without the need for Master controllers and/or timingreference signals and/or frequency reference signals. No special controlStation Interface, and/or arbitration Station Interface, and/or MasterStation Interface is required. When a Station Interface receives amessage it checks for the origin of the message. If the message camefrom the Station Interface which is its immediate predecessor on theATTS, then it is that Station Interface's turn to transmit as soon asthe incoming message has been competed.

The methods and devices disclosed herein can be used on a variety ofdifferent networks, composed of the same and/or different transmissionmedia, and are preferably, but not necessarily, implemented using freespace transmission. However, omnidirectional and segmented branchednetworks are possible and contemplated. For example, but not limited to,with an omnidirectional network the messages from each Station Interfaceare routed in all directions over the network so that each message canbe received, where permitted, at every Station Interface. The speed withwhich each Station Interface receives a message is limited only by therespective propagation delay through the transmission media from thetransmitting Station Interface. As mentioned herein, the order in whichStation Interfaces have the authority to transmit preferably progressesin one direction at a time along the ATTS, connecting all active StationInterfaces forming that segment of the network. The directions or orderin which the ATTS progresses between the Station Interfaces should notbe confused with the directional nature in which the messages travel inthe communications media and which are limited by physical constraintsof the network connections and the network environment.

FIG. 1 illustrates a snapshot planar cross-section of an exemplary BSTTSnetwork 100 embodiment among stations broadcasting in 3-dimensional freespace. Initial studies have shown that embodiments of the presentinvention can use much, possibly up to 99%, of the theoretical bandwidthavailable to network users, with latencies being a small fraction ofthose inherent in even the most expensive switched networks.

Only five mobile stations 101 (101 a, 101 b, 101 c, 101 d and 101 e) areshown for simplicity. Many additional fixed and/or mobile workstationsare easily connected to network 100 without loss of generality orfunctionality. The environment is not limited to the omnidirectionaltransmission pattern presented by FIG. 1 nor to equal directional energytransmission patterns.

For the free space network 100 it is possible to compute all thepossible transmission sequences combinations (5!=120) in order todetermine the MPT ATTS, which is given byMPT₁₀₀=t_(AB)+t_(BC)+t_(CD)+t_(DE)+t_(ED)+t_(DC)+t_(CB)+t_(BA). Fornetwork 100 the ATTS IDM Message Cycle is MPT₁₀₀.

The five stations 101 are shown in the process of executing a normal IDMMessage cycle. At the time when one, two or all stations 101 processreceived messages 300, the reception of the messages 300 may beacknowledged by one, two or all stations 101.

For convenience of explanation, and in order to facilitateunderstanding, unless otherwise specified, ATTS transmissions areauthorized in station alphabetical order: ATTS₁₀₀=<station 101 a,station 101 b, station 101 c, station 101 d, station 101 e>. In anactual environment, the order might be different, such as 101 a, 101 d,101 b, 101 c, and 101 e.

Assume now that station 101 a has authority, and begins, to transmitmessage 300 a 1. As soon as message 300 a 1 reaches station 101 b,station 101 b sends message 300 b 1. As soon as message 300 b 1 reachesstation 101 c, station 101 c sends message 300 c 1. As soon as message300 c 1 reaches station 101 d, station 101 d sends message 300 d 1. Assoon as message 300 d 1 reaches station 101 e, station 101 e sendsmessage 300 e 1. As station 101 e is the ATTS₁₀₀ limit, or end point,station 101 e immediately sends message 300 e 2 back toward station 101d. As soon as message 300 e 2 reaches station 101 d, station 101 d sendsmessage 300 d 2. As soon as message 300 d 2 reaches station 101 c,station 101 c sends message 300 c 2. As soon as message 300 c 2 reachesstation 101 b, station 101 b sends message 300 b 2. As soon as message300 b 2 reaches station 101 a, station 101 a is ready to send, andsends, message 300 a 2. This completes a full cycle as each station hastransmitted two messages. As station 101 a is the ATTS₁₀₀ limit, station101 a sends message 300 a 3 immediately following message 300 a 2.

For illustrative purposes only, to show the different transmissions, andnot indicate any speed, direction, strength, etc., of any message,station 101 a is shown as being at the center of messages 300 a 1 and300 a 2, station 101 b is shown as being at the center of messages 300 b1 and 300 b 2, etc.

One may look at FIG. 1 as showing that messages 300 a 1-300 e 1 and 300e 2-300 c 2 have now been received by, and propagated beyond, allstations 101, but that message 300 b 2 has just been transmitted and hasnot yet reached the closest neighbor station 101 a. Thus, a first IDMMessage Cycle might be the following: station 101 a transmits message300 an; then station 101 b transmits message 300 bn; then station 101 ctransmits message 300 cn; then station 101 n transmits message 300 dn;then station 101 e transmits message 300 _(en); then station 101 etransmits message 300 _(em); then station 101 d transmits message 300_(dm); then station 101 c transmits message 300 _(cm); then station 101b transmits message 300 _(bm); then station 101 a transmits message 300_(am); where n is a odd integer (in the example above n is theinteger 1) and m=n+1, an even integer (in the example above m is theinteger 2). Continuous IDM Message cycles for network 100 repeat ATTS₁₀₀until one and/or all stations 101 cease to transmit. Note that eachstation, including the starting and ending stations, has had theopportunity to transmit two times, the same as any other station.

Examining the network 100 state along any transmission radius, with thestation of choice at the center, such as, but not limited to, that shownas cross-section 200, it is observed that the bandwidth (measured inthis case on a radius from station 101 b) is optimally used, beingoccupied either by data (one or messages 300) or by the propagation timethrough free space PT₁₀₀=107 a+107 b+107 c+107 d+107 e+107 l+107 m+107 nalong the ATTS₁₀₀ transmission media route from station 101 a-to-station101 b-to-station 101 c-to-station 101 d-to-station 101 e and then backfrom station 101 e-to-station 101 d-to-station 101 c-to-station 101b-to-station 101 a.

FIG. 2 illustrates the energy distribution along cross-section 200 withstation 101 a to the left and the outer edge of message 300 a 1 to theright. The total propagation time through free space on radialcross-section 200, or any other radial cross-section, adds up to twicethe time of the transmission propagation time along the transmissionmedia route from station 101 a-to-station 101 b-to-station 101c-to-station 101 d-to-station 101 e.

FIG. 3 illustrates a typical BSTTS message 300 as it might appear on atransmission media 600. A BSTTS message 300 may be, and is preferably,formed by adding one or more fields to the standard message packet usedby many system embodiments and known to one skilled in the art.

Unlike, for example but not limited to, standard Ethernet where aminimum message length is required for network integrity, a BSTTSnetwork does not require that messages 300 conform to some minimummessage length and/or to a fixed message length. Typical of any digitalpacket network, messages 300 include a header, an information payload,and a trailer. According to the present invention, a station couldtransmit as long as desired and release the communications media 600only when it has transmitted everything. In practice, physical andoperational constraints may require that the size of the payload of anyone message be restricted to some maximum value, and a longer messagemay be subdivided into shorter messages to meet this maximum messagesize.

This maximum message size may be determined by the specificenvironmental criteria, for example, but not limited to: limitationsimposed by physical constraints in the Station Interface devices betweenthe station and the transmission media 600; fair access to thetransmission media 600 by all stations, bit error rate of thetransmission media 600; and Contract Quality of Service.

In one embodiment, when a Station Interface does not have any data fromits associated station to transmit for a payload 319, the StationInterface transmits a message 300 whose payload 319 reports the currentstatistics and status of the Station Interface, thereby releasing unusedbandwidth and making the maximum amount of effective bandwidth availableto all transmitting stations in the network. In another embodiment theStation Interface transmits a message 300 whose payload 319 reports thechanges to its statistics and status. In yet another embodiment theStation Interface transmits a minimum message 300.

The transmission of a status or minimum message 300 provides certainbenefits. For example, but not limited to, this keeps wireless, opticaland electrical phase lock loops “locked”; it informs all StationInterfaces that the Station Interface and its station are functioningproperly even though the Station Interface does not have a payload 319to send; it permits the health of each Station Interface and station tobe easily determined by all Station Interfaces and stations; it informsthe next Station Interface in the ATTS of its authority to transmit; itenables dynamic testing of the transmission media 600 physical layerwhile it is operating, in contrast to other protocols, which must betaken off-line to test the physical layer; and it eliminates the needfor separate mechanisms and/or separate bandwidth limiting messages todetermine the health of the operating network.

A typical BSTTS message 300 preferably consists primarily of augmentedstandard packet information, such as, but not limited to: a header, apayload, and a trailer. A header may, for example, include the followingfields: start-of-leader 301, leader 303, start-of-routing 305, routing307, start-of-type 309, message type 311, start-of-time-and-status 313,and time-and-status 315. The start-of-leader 301 and leader 303 fieldsmay be considered to be a preamble. A payload may, for example, includethe following fields or message-elements: start-of-payload 317, anduser-payload 319. A trailer may, for example, include the followingfields or message elements: start-of-trailer 321, trailer 323, andend-of-trailer 325.

The preamble permits the Station Interface detecting sensors tosynchronize with the frequency and/or phase of a particular message, forexample, but not limited to, when clock recovery transmission isemployed. The length of the preamble is, for example, but not limitedto, a function of the performance of the transmission media and thesynchronization mechanism associated with the specific transmissionmedia and can be specified as a system initialization parameter. Thestart-of-leader 301, in one embodiment, contains zero bits.

The routing information (message-elements: start-of-routing 305 androuting 307) indicates both the local destination(s) and the ultimatedestination(s) of the payload. The routing information can be thought ofas an address, which identifies, but is not limited to, such informationas transmitting device addresses, receiving device addresses, devicenetwork segments, device network associations, and device frequencies ofoperation. The start-of-routing 305 in one embodiment contains zerobits.

The Station Interfaces may use message category (message-elements:start-of-type 309 and message type 311) and timing and statusinformation (message-elements: start-of-time-and-status 313 andtime-and-status 315) to organize and to maintain the ATTS. Thestart-of-type 309 and start-of-time-and-status 313 fields in oneembodiment of the present invention contains zero bits.

The message timing and status information (components:start-of-time-and-status 313 and time-and-status 315) provides eachStation Interface with the capability to acknowledge the receipt of anyand/or all specific messages, thereby enabling assured delivery ofinformation to any station, without extra message traffic and within oneIDM Message Cycle. This information may also be used to determine thepropagation time.

The start-of-payload 317 indicates that the user information contentfollows. The start-of-payload may be used to control Station Interfaceexecution. The start-of-payload 317 field in one embodiment of thepresent invention contains zero bits.

The payload 319 contains the station information for transmission andreception, which may be sized for each individual transmission from zerobits to some implementation-dependent maximum value of bits, and isdelivered and received according to the routing information 307.

The trailer permits each Station Interface, which processes BSTTSmessage 300 structure, to verify the integrity of the header and payloadinformation. The end-of-trailer 325 field may be used to tune theperformance of the transmission media. The start-of-trailer 321 andend-of-trailer 325 fields in one embodiment contains zero bits.

The minimum message 300, in one embodiment, consists of the preamble 303and trailer 323. The BSTTS message 300 control elements (start-ofpreamble 301, routing 305, start-of-type 309,start-of-time-and-start-of-status 313, start-of-payload 317,start-of-trailer 321, and end-of-trailer 325) contain information thatmay be used by or to direct a Station Interface to perform serial and/orparallel processing of message 300.

There are numerous instances herein where Station Interfaces transmit orsend a message 300 and/or a message 300 propagates throughout the BSTTSnetwork, for example, but not limited to, BSTTS networks: 100, 400, 500,and 800. They are variously referred to herein as “Sends Messages” or“Transmits Message” or “Transmitting Message” but, unless otherwiseindicated, generally have the same meaning and effect. For example, thephrase “Transmits Message 300” preferably means that a Station Interfacetransfers message 300 from its internal storage and couples the message300 onto one, two or a plurality of transmission media 600. Note that,because ATTS defined Station Interfaces generally do not have theauthority to transmit until the detection of message end-of-trailer 325,there are neither collisions nor a need to perform arbitration whilemessage 300 is delivered throughout the network.

One benefit provided is that the duty cycle of the Station Interfacetransmitters will be lower than in conventional networks because theATTS specifies the times when the transmitter active elements areenergized. In particular, transmission may begin once the end-of-trailer325 from the predecessor station interface has been received, or when atimeout has occurred without a transmission from the predecessor stationinterface. This in turn indicates that the Station Interfacetransmitters may have a higher Mean Time Between Failure, resulting inmore cost effective user networks.

Likewise, there are numerous instances herein wherein Station Interfacesreceive and process messages 300, which are associated with astart-of-preamble 301. These instances are variously referred to hereinas “Receive Message”, or “Receive Messages”, or “Receives Message”, or“Receives Messages, or “Receiving Message” but, unless otherwiseindicated, generally have the same meaning and effect. For example, thephrase “Receive Message 300” preferably means that a Station Interfacedetects a start-of-preamble 301, accepts (inputs) message 300 andperforms certain processing, such as, but limited to the following:reading and then resetting its message-arrival-timer; and determiningwhat action to take with respect to the message.

If a Station Interface determines, from received routing element 307,that the payload 319 is addressed to it but the Station Interface doesnot have the capability to accept the message 300, then StationInterface does not accept the payload 319 and does not acknowledge thereceipt of the message 300. This failure to acknowledge receiptindicates, for example, that the sending Station Interface shouldre-transmit the message 300 during a future IDM Message Cycle. If themessage 300 is addressed to the Station Interface, and the StationInterface has the ability to accept the message, then the StationInterface accepts and acknowledges receipt of the message 300. In onepreferred embodiment, even if the message 300 is not addressed to it,and/or the Station Interface cannot accept the message, the StationInterface may process the message 300 to measure transmission media 600quality.

An inability to accept a message may be because, for example, themessage buffers in the Station Interface are full and/or the messagebuffers in the Station are full, or the Station is not in operation atthat time.

Other forms of processing may occur, if desired, when transmittingand/or receiving messages. One benefit provided is that messageacknowledgement receipts can be formed, transmitted and received withinone IDM Message Cycle, rather than, for example, requiring the use ofmultiple bandwidth limiting messages requiring multiple transmissionsand/or separate signaling paths.

For convenience of explanation, it is preferable to start with referenceto a simple network with stations connected using a simple bus. FIG. 4Aillustrates a simple network 400 showing station 101 a connected viatransmission media 600 b to Station Interface 501 a and station 101 bconnected via transmission media 600 c to Station Interface 501 b.Station Interface 501 a is connected to Station Interface 501 b viatransmission media 600 e. Station 101 a messages transmitted by StationInterface 501 a travel simultaneously in both directions: 1) direction405 a along the transmission media 600 d and 2) direction 405 b alongthe transmission medium 600 e, being detected some propagation timelater t_(AB) 107 (FIG. 4A) by the other station 101 b Station Interface501 b. Similarly, station 101 b messages transmitted by StationInterface 501 b travel simultaneously in both directions: 1) direction405 d along transmission media 600 f and 2) direction 405 d along theshared transmission medium 600 e, being detected some propagation timelater t_(AB) 107 by the other station 101 a Station Interface 501 a.This communication may be, for example, half-duplex communication, i.e.,two-way communication, one direction at a time via one transmissionmedia 600.

Parallel duplex and multiplex communications, over two or a plurality oftransmission media 600 between two or a plurality of Station Interfacesand a two or a plurality of transmission media 600 connected among aplurality of Station Interfaces, using the same and/or differenttransmission media 600, may also be efficiently organized, controlled,optimized, and operated using the techniques disclosed herein.

For this simple example it is easily possible to compute all thepossible combinations (2!=2) of network 400 transmission sequences inorder to determine the exact solution that has the MPT for the network400: MPT=t_(AB)+t_(BA)=2t_(AB). Thus, for network 400 the IDM MessageCycle MPT is 2t_(AB).

In FIGS. 4B-4C, and 5A-5G, vertically crosshatched message-elementsrepresent the times when a message 300 is being transmitted by a StationInterface, horizontally crosshatched message-elements represent thepropagation times between messages 300, and non-crosshatchedmessage-elements represent the times when Station Interfaces processmessages 300.

Referring to FIGS. 4A-4C, ATTS₄₀₀ and ATTS₄₀₁ are, in this example,equivalent, exact, and equal ATTS's, with MPT that could control IDMMessage Cycles 407 (407 a, 407 b, 407 c, 407 d, 407 e, and 407 f). Theordered set notation ATTS₄₀₀=<Station Interface 501 a, Station Interface501 b> means, in this example, that Station Interfaces 501 a and 501 bare the network end points, and so each get two transmissions in an IDMmessage cycle, one transmission as the end receiving point, and onetransmission as the transmitting starting point. Station Interface 501 awill begin the cycle so, with reference to network 400, forwarddirection transmissions: the first ATTS₄₀₀ defined Station Interface 501a transmits message 300 a 1; and, after a propagation time delay oft_(AB) 107, Station Interface 501 b processes message 300 a 1, and,because Station Interface 501 a is the predecessor of Station Interface501 b, Station Interface 501 b transmits message 300 b 1; therebycompleting the first forward direction transmission. “Forward” and“Reverse” refer to the ATTS sequence ordering, not to the physicaldirection. With reference to network 400, reverse directiontransmissions: the last ATTS₄₀₀ defined Station Interface 501 btransmits message 300 b 2 and begins the first reverse directiontransmission. Next, after a propagation time delay of t_(AB) 107,Station Interface 501 a processes message 300 b 2. Next, because StationInterface 501 b is the predecessor of Station Interface 501 a, StationInterface 501 a transmits message 300 a 2, thereby completing the firstreverse direction transmission and IDM Message Cycle 407 a.

In this example, ATTS₄₀₁=<Station Interface 501 b, Station Interface 501a> so, with reference to network 400, Station Interface 501 b will beginthe cycle. The forward direction transmissions are then: the firstATTS₄₀₁ defined Station Interface 501 b transmits message 300 b 1; and,after a propagation time delay of t_(AB) 107, Station Interface 501 aprocesses message 300 b 1, and because Station Interface 501 b is thepredecessor of Station Interface 501 a, Station Interface 501 atransmits message 300 a 1 completing the first forward directiontransmissions. With reference to network 400, reverse directiontransmissions: the last ATTS₄₀₁ defined Station Interface 501 atransmits message 300 a 2; beginning the first reverse directiontransmissions. Then, after a propagation time delay of t_(AB) 107,Station Interface 501 b processes message 300 a 2, and, because StationInterface 501 a is the predecessor of Station Interface 501 b, StationInterface 501 b transmits message 300 b 2; thereby completing the firstreverse direction transmissions and also completing the IDM MessageCycle 407 d.

FIG. 4B shows network 400 events for ATTS₄₀₀ IDM message Cycles 407 a,407 b, and 407 c as detected and processed at Station Interface 501 a.As defined by ATTS₄₀₀ Station Interface 501 a commences IDM messageCycle 1 407 a by transmitting message 300 a 1. Station Interface 501 asets its message-arrival-timer to 2t_(AB) 107 a. At an approximateelapsed time interval 2t_(AB) 107 a Station Interface 501 a receivesmessage 300 b 1. Next, from its ATTS₄₀₀ copy, Station Interface 501 aknows to wait for and to receive message 300 b 2 for the reversedirection ATTS transmission and then, because Station Interface 501 b isStation Interface 501 a predecessor, Station Interface 501 a transmitsmessage 300 a 2 completing IDM message Cycle 1 407 a. As StationInterface 501 a is the first ATTS₄₀₀ defined Station Interface, it thentransmits message 300 a 3, thereby commencing IDM message Cycle 2 407 b.Station Interface 501 a sets its message-arrival-timer to 2t_(AB) 107 a.At an approximate elapsed time interval 2t_(AB) 107 a, Station Interface501 a receives message 300 b 3. Then, from its ATTS₄₀₀ copy, StationInterface 501 a knows to wait for and to receive message 300 b 4 andthen, because Station Interface 501 b is Station Interface 501 apredecessor, Station Interface 501 a transmits message 300 a 4, therebycompleting IDM message Cycle 2 407 b. As Station Interface 501 a is thefirst ATTS₄₀₀ defined Station Interface, it immediately transmitsmessage 300 a 5 starting IDM message Cycle 3 407 c. Station Interface501 a sets its message-arrival-timer to 2t_(AB) 107 a. At an approximateelapsed time interval 2t_(AB) 107 a Station Interface 501 a receivesmessage 300 b 5. Next, from its ATTS₄₀₀ copy Station Interface 501 aknows to wait for and to receive message 300 b 6 and then, becauseStation Interface 501 b is Station Interface 501 a predecessor, StationInterface 501 a transmits message 300 a 6, thereby completing IDMmessage Cycle 3 407 c. As Station Interface 501 a is the first ATTS₄₀₀defined Station Interface, it immediately transmits message 300 a 7,thereby commencing the next IDM message Cycle. Station Interface 501 asets its message-arrival-timer to 2t_(AB) 107 a and awaits the arrivalmessage 300 b 7 from Station Interface 501 b.

Similarly, FIG. 4C shows network 400 events for ATTS₄₀₀ IDM messageCycles 407 d, 407 e, and 407 f as detected and processed by StationInterface 501 b. Initially, Station Interface 501 b samples transmissionmedia 600 e for a message 300 indicated by the arrival of itsstart-of-header 301. The time interval t_(AB) 107 Station Interface 501b waits from Station Interface 501 a transmission of message 300 a 1 forits arrival is illustrated at the start of FIG. 4C. Time interval t_(AB)107 is the time shift between events at the two Station Interfaces 501 aand 501 b due to media 600 e propagation time between them. IDM messageCycle 1 407 d commences when Station Interface 501 b receives message300 a 1 and then, because Station Interface 501 a is Station Interface501 b predecessor, Station Interface 501 b transmits message 300 b 1. AsStation Interface 501 b is the last ATTS₄₀₀ defined station, it thentransmits message 300 b 2. Station Interface 501 b sets itsmessage-arrival-timer to 2t_(AB) 107 a. At an approximate elapsed timeinterval 2t_(AB) 107 a, Station Interface 501 b receives message 300 a2. Next, from its ATTS₄₀₀ copy, Station Interface 501 b knows to waitfor and to receive message 300 a 3. IDM message Cycle 2 407 e begins asStation Interface 501 b receives message 300 a 3 and then, becauseStation Interface 501 a is Station Interface 501 b predecessor, StationInterface 501 b transmits message 300 b 3. As the last ATTS₄₀₀ definedStation Interface, Station Interface 501 b then transmits message 300 b4. Station Interface 501 b sets its message-arrival-timer to 2t_(AB) 107a. At an approximate elapsed time interval 2t_(AB) 107 a StationInterface 501 b receives message 300 a 4. Next, from its ATTS₄₀₀ copy,Station Interface 501 b knows to wait for and to receive message 300 a5. IDM message Cycle 2 407 f begins as Station Interface 501 b receivesmessage 300 a 5 and then, because Station Interface 501 a is StationInterface 501 b predecessor, Station Interface 501 b transmits message300 b 5. As the last ATTS₄₀₀ defined Station Interface, StationInterface 501 b then transmits message 300 b 6. Station Interface 501 asets its message-arrival-timer to 2t_(AB) 107 a. At an approximate time2t_(AB) 107 a Station Interface 501 b receives message 300 a 6. Thiscompletes IDM message Cycle 3 407 f. From its ATTS₄₀₀ copy, StationInterface 501 b knows to wait for and to receive message 300 a 7.Station Interface 501 b commences the next IDM message Cycle bybeginning to receive message 300 a 7.

Thus, both FIG. 4B and FIG. 4C illustrate normal ATTS controlled IDMMessage Cycles 407 (407 a, 407 b, 407 c, 407 d, 407 e and 407 f)operations between Station Interfaces 501 a and 501 b to deliverinformation between the stations 101 a and station 101 b. As can be seenfrom FIG. 4B and FIG. 4C, Station Interfaces 501 a and 501 b exchangetwo messages each in a total elapsed time consisting of the time each ofthe four messages 300 a 1, 300 b 1, 300 b 2 and 300 a 2 are on thetransmission media 600 e, plus two propagation delays MPT=2t_(AB) 107 a.This is a most efficient manner for network 400 to communicate over ashared transmission media 600.

Repetitive transmission at the ATTS limits (network end points) ensuresequal access for all stations during each IDM Message Cycle. When thatStation Interface is at one of the ATTS ordered set limits it implementsbuffering of at least two messages 300 and sends the buffered messages300 back-to-back. Thus, there need be no penalty for a station being atan ATTS ordered set limits.

Subject to transmission media considerations and Station Interfaceimplementation considerations, and except for the obvious physicallimitation of the propagation delay among stations, the header, thestart-of-payload 317, and the trailer, this implementation enables thebandwidth of the transmission media 600 to be fully utilized by the userpayload.

The present invention is not limited to the simple case of FIGS. 4A-4Cbut also may be applied to, for example, networks that broadcast in freespace, networks with larger numbers of stations, networks with one, twoand a plurality of branches with larger numbers of stations, networkswith one, two or a plurality of interconnecting transmission media 600,and networks composed of mobile and/or fixed stations.

FIGS. 5A-5G illustrate a larger network 500 and the operation thereof.FIG. 5A illustrates an exemplary branched network 500, which is composedof six stations 101 (101 a, 101 b, 101 c, 101 d, 101 e and 101 f).Stations 101 may be of any arbitrary complexity and may be connected viaone or more of the same or different transmission media 600 to theirStation Interfaces 501 a, 501 b, 501 c, 501 d, 501 e and 501 f. StationInterfaces 501 a, 501 b, 501 c, 501 d, 501 e and 501 f may be connectedto transmission media 600 a in functional equivalent implementations.Transmission media 600 and 600 a may consist of one or more transmissionmedia. In the exemplary embodiment shown, the six stations 101 are shownconnected via transmission media to their respective Station Interfaces501, which are, in turn, interconnected by physical transmission mediasegments 600 a 1, 600 a 2, 600 a 3, 600 a 4, 600 a 5, 600 a 6, 600 a 7,and 600 a 8.

Multiple different BSTTS messages 300 may be simultaneously propagatingalong different transmission media 600 a segments and transmission media600. Additionally, messages 300 transmitted by Station Interfaces 501 a,501 b, 501 c, 501 d, 501 e and 501 f within branched network 500 canpotentially travel simultaneously in multiple directions alongtransmission media 600 a. For example, but not limited to, messages 300transmitted by Station Interface 501 d within branched network 500initially travel simultaneously along transmission media segments 600 a4 and 600 a 5, messages 300 transmitted by Station Interface 501 cwithin branched network 500 initially travel simultaneously alongtransmission media segments 600 a 3 and 600 a 4, and messages 300transmitted by Station Interface 501 b within branched network 500initially travel simultaneously along transmission media segments 600 a2, 600 a 3 and 600 a 6 Station Interface 501 a messages 300 atransmitted within branched network 500 initially travel simultaneouslyalong transmission media segments 600 a 1 and 600 a 2. Station Interface501 e messages 300 e transmitted within branched network 500 initiallytravel simultaneously along transmission media segments 600 a 6 and 600a 7. Station Interface 501 f messages 300 f transmitted within branchednetwork 500 initially travel simultaneously along transmission mediasegments 600 a 7 and 600 a 8.

In addition the following energy propagation occurs at Station Interface501 b. Energy propagating along transmission media segment 600 a 6 toStation Interface 501 b is also propagating to Station Interface 501 b,to transmission media segment 600 a 2, and transmission media segment600 a 3. Energy propagating along transmission media segment 600 a 3 toStation Interface 501 b is also propagating to Station Interface 501 b,to transmission media segment 600 a 2, and transmission media segment600 a 6. Energy propagating along transmission media segment 600 a 2 toStation Interface 501 b is also propagating to Station Interface 501 b,to transmission media segment 600 a 3, and transmission media segment600 a 6.

FIGS. 5B-5G illustrate the operation of an MPT ATTS₅₀₀ as transmitted,received and processed by Station Interfaces 501 d, 501 c, 501 b, 501 a,501 e and 501 f, respectively, and also illustrate the timing of anormal IDM Message Cycle across the simple branched network 500. Thisillustrates that the lost bandwidth on the transmission media 600 a isdue to the accumulated propagation delays 107 a 107 g, 107 h, 107 j, and107 k among Station Interfaces 501 a, 501 b, 501 c, 501 d, 501 e and 501f. Thus, the branched network 500 operates at optimum throughputefficiency, because the ATTS₅₀₀ operates with MPT.

The ATTS₅₀₀ transmitted message sequence associated with FIGS. 5B-5G maybe described as follows. In this example, the first ATTS₅₀₀ ordered setmember, Station Interface 501 d commences IDM message Cycles 1 407 g,407 h, 407 l, 407 j, 407 k, and 4071 by transmitting message 300 d 1 forone or all other Station Interfaces 501 a, 501 b, 501 c, 501 e, and 501f to receive message 300 d 1. Following propagation time t_(DC) 107 l,Station Interface 501 c receives message 300 d 1 from Station Interface501 d. Then, as the next ATTS₅₀₀ ordered set member, Station Interface501 c transmits message 300 c 1 for one or all other Station Interfaces501 a, 501 b, 501 d, 501 e, and 501 f to receive message 300 c 1. Attime t_(DC) 107 l+t_(CB) 107 m, Station Interface 501 b receivesmessages 300 d 1 from Station Interface 501 d and message 300 c 1 fromStation Interface 501 c. As the next ATTS₅₀₀ ordered set member, StationInterface 501 b transmits message 300 b 1, for one or all other StationInterfaces 501 a, 501 c, 501 d, 501 e, and 501 f to receive message 300b 1. At time t_(DC) 107 l+t_(CB) 107 m+t_(BA) 107 n, Station Interface501 a receives message 300 d 1 from Station Interface 501 d, message 300c 1 from Station Interface 501 c and message 300 b 1 from StationInterface 501 b. As the next ATTS₅₀₀ order set member, Station Interface501 a transmits message 300 a 1, for one or all other Station Interfaces501 b, 501 c, 501 d, 501 e, and 501 f to receive message 300 a 1. Attime t_(DC) 107 l+t_(CB) 107 m+t_(BE) 107 o, Station Interface 501 ereceives message 300 d 1 from Station Interface 501 d, message 300 c 1from Station Interface 501 c and message 300 b 1 from Station Interface501 b, and after propagation delay 2t_(BA) 107 a, Station Interface 501e receives message 300 a 1 from Station Interface 501 a. As the nextATTS₅₀₀ ordered set member, Station Interface 501 e, transmits message300 e 1, for one or all other Station Interfaces 501 a, 501 b, 501 c,501 d, and 501 f to receive message 300 e 1. At time t_(DC) 107 l+t_(CB)107 m+t_(BE) 107 o+t_(EF) 107 p, Station Interface 501 f receivesmessages 300 d 1, 300 c 1, 300 b 1, and after propagation delay 2t_(BA)107 a, receives messages 300 a 1 and 300 e 1. As the next ATTS₅₀₀ordered set member, Station Interface 501 f then transmits message 300 f1, for one or all other Station Interfaces 501 a, 501 b, 501 c, 501 e,and 501 f to receive message 300 f 1.

In this simple and not limiting example, given that Station Interface501 f is the sixth and last ATTS₅₀₀ defined Station Interface 501 f, itimmediately reverses the ATTS and transmits message 300 f 2, for one orall other Station Interfaces 501 a, 501 b, 501 c, 501 d, and 501 e toreceive message 300 f 2. At a time t_(FE) later, Station Interface 501 ereceives message 300 f 1, and as the next ATTS₅₀₀ ordered set member,transmits message 300 e 2, for one or all other Station Interfaces 501a, 501 b, 501 c, 501 d, and 501 f to receive message 300 e 2. Followingpropagation time t_(EB)+t_(BA) 107 n, Station Interface 501 a receivesmessage 300 e 2, and as the next ATTS₅₀₀ ordered set member, transmitsmessage 300 a 2, for one or all other Station Interfaces 501 b, 501 c,501 d, 501 e, and 501 f to receive message 300 a 2. Followingpropagation time t_(AB) 107 Station Interface 501 b receives message 300a 2, and as the next ATTS₅₀₀ ordered set member, transmits message 300 b2, for one or all other Station Interfaces 501 a, 501 b, 501 c, 501 e,and 501 f to receive message 300 b 2. Following propagation time t_(BC),Station Interface 501 c receives message 300 a 2, and as the nextATTS₅₀₀ ordered set member, transmits message 300 c 2, for one or allother Station Interfaces 501 a, 501 b, 501 d, 501 e, and 501 f toreceive message 300 c 2. Following propagation time t_(CD), StationInterface 501 d receives message 300 c 2, and as the next ATTS₅₀₀ordered set member, transmits message 300 d 2, for one or all otherStation Interfaces 501 a, 501 b, 501 c, 501 e, and 501 f to receivemessage 300 d 2. This transmission completes all IDM message Cycle 1's407 g, 407 h, 407 l, 407 j, 407 k, and 4071. In this example, StationInterface 501 d is the initial ATTS₅₀₀ Station Interface, so it theninitiates the next IDM message Cycle by transmitting message 300 d 3.

FIG. 5B illustrates ATTS₅₀₀ IDM message Cycle 1 407 g as detected andprocessed by Station Interface 501 d and is described as follows. At IDMmessage Cycle commencement, such as, but not limited to, IDM messageCycle 1 407 g, as the first ATTS₅₀₀ ordered set member, StationInterface 501 d transmits message 300 d 1, Station Interface 501 d setsa message-arrival-timer to approximately 2t_(CD) 107 g, and StationInterface 501 d awaits the next ATTS₅₀₀ message 300 c 1 arrival. Afterapproximate elapsed time interval 2t_(CD) 107 g, Station Interface 501 dreceives message 300 c 1. In the forward ATTS₅₀₀ direction StationInterface 501 d, is the first ATTS₅₀₀ ordered set member and does nothave a predecessor, so Station Interface 501 d does not transmit,Station Interface 501 d sets a message-arrival-timer to approximately2t_(BC) 107 h, and Station Interface 501 d awaits the next ATTS₅₀₀message 300 b 1 arrival. After approximate elapsed time interval 2t_(BC)107 h, Station Interface 501 d receives message 300 b 1. In the forwardATTS₅₀₀ direction Station Interface 501 d does not have a predecessor,so Station Interface 501 d does not transmit, Station Interface 501 dagain sets a message-arrival-timer to approximately 2t_(AB) 107 a, andStation Interface 501 d awaits the next ATTS₅₀₀ message 300 a 1 arrival.After approximate elapsed time interval 2t_(AB) 107 a, Station Interface501 d receives message 300 a 1. In the forward ATTS₅₀₀ direction StationInterface 501 d does not have a predecessor, so Station Interface 501 dstill does not transmit, Station Interface 501 d sets amessage-arrival-timer to approximately 2t_(BE) 107 j, and StationInterface 501 d awaits the next ATTS₅₀₀ message 300 e 1 arrival. Afterapproximate elapsed time interval 2t_(BE) 107 j, Station Interface 501 dreceives message 300 e 1. In the forward ATTS₅₀₀ direction StationInterface 501 d does not have a predecessor, so Station Interface 501 ddoes not transmit, Station Interface 501 d sets a message-arrival-timerto approximately 2t_(EF) 107 k, and Station Interface 501 d awaits thenext ATTS₅₀₀ message 300 f 1 arrival. After approximate elapsed timeinterval 2t_(EF) 107 k, Station Interface 501 d receives message 300 f1, which completes ATTS₅₀₀ forward direction communications.

Station Interface 501 d determines from its ATTS₅₀₀ copy that StationInterface 501 f is the last ATTS₅₀₀ ordered set member. StationInterface 501 d reverses ATTS₅₀₀ direction and Station Interface 501 dreceives messages 300 f 2 and 300 e 2. In the reverse ATTS₅₀₀ direction,message 300 e 2 source Station Interface 501 e is not Station Interface501 d's predecessor (Station Interface 501 c is), so Station Interface501 d does not transmit, Station Interface 501 d sets amessage-arrival-timer to approximately 2t_(AB) 107 a, and StationInterface 501 d awaits the next ATTS₅₀₀ message 300 a 2 arrival. Afterapproximate elapsed time interval 2t_(AB) 107 a, Station Interface 501 dreceives messages 300 a 2, 300 b 2, and 300 c 2. In the reverse ATTS₅₀₀direction, message 300 c 2 is from Station Interface 501 d predecessor(Station Interface 501 c), so Station Interface 501 d transmits message300 d 2 thereby completing IDM message Cycle 1 407 g and completingATTS₅₀₀ reverse direction communications. Station Interface 501 d is theinitial ATTS₅₀₀ member, so Station Interface 501 d reverses ATTS₅₀₀ toforward direction and Station Interface 501 d then transmits message 300d 3 commencing the next IDM message Cycle.

FIG. 5C illustrates ATTS₅₀₀ IDM message Cycle 1 407 h as detected andprocessed by Station Interface 501 c and may be described as follows. AtIDM message Cycle commencement, such as, but not limited to, IDM messageCycle 1 407 h, Station Interface 501 c is not first ATTS₅₀₀ StationInterface 501 d, so Station Interface 501 c samples transmission media600 a signals, and awaits the next ATTS₅₀₀ message 300 d 1 arrival.After approximate elapsed time interval t_(DC) 107 l, Station Interface501 c receives message 300 d 1. In the forward ATTS₅₀₀ direction,message 300 d 1 is from Station Interface 501 c's ATTS₅₀₀ predecessor(Station Interface 501 d), so Station Interface 501 c transmits message300 c 1, Station Interface 501 c sets a message-arrival-timer toapproximately 2t_(BC) 107 h, and Station Interface 501 c awaits the nextATTS₅₀₀ message 300 b 1 arrival. After approximate elapsed time interval2t_(BC) 107 h, Station Interface 501 c receives message 300 b 1. In theforward ATTS₅₀₀ direction message 300 b 1 source Station Interface 501 bis not Station Interface 501 c's predecessor (Station Interface 501 d),so Station Interface 501 c does not transmit, Station Interface 501 csets a message-arrival-timer to approximately 2t_(AB) 107 a, and StationInterface 501 c awaits the next ATTS₅₀₀ message 300 a 1 arrival. Afterapproximate elapsed time interval 2t_(AB) 107 a, Station Interface 501 creceives message 300 a 1. In the forward ATTS₅₀₀ direction message 300 a1 source Station Interface 501 a is not Station Interface 501 c'spredecessor (Station Interface 501 d), so Station Interface 501 c doesnot transmit, Station Interface 501 c sets a message-arrival-timer toapproximately 2t_(BE) 107 j, and Station Interface 501 c awaits the nextATTS₅₀₀ message 300 e 1 arrival. After approximate elapsed time interval2t_(BE) 107 j, Station Interface 501 c receives message 300 e 1. In theforward ATTS₅₀₀ direction message 300 e 1 source Station Interface 501 eis not Station Interface 501 c's predecessor (Station Interface 501 d),so Station Interface 501 c does not transmit, Station Interface 501 csets a message-arrival-timer to approximately 2t_(EF) 107 k, and StationInterface 501 c awaits the next ATTS₅₀₀ message 300 f 1 arrival. Afterapproximate elapsed time interval 2t_(EF) 107 k, Station Interface 501 creceives message 300 f 1, which completes ATTS₅₀₀ forward directioncommunications.

Station Interface 501 c determines from its ATTS₅₀₀ copy that StationInterface 501 f is the last ATTS₅₀₀ ordered set member. StationInterface 501 c reverses ATTS₅₀₀ direction and Station Interface 501 creceives messages 300 f 2 and 300 e 2. In the reverse ATTS₅₀₀ direction,message 300 e 2 source Station Interface 501 e is not Station Interface501 c's predecessor (Station Interface 501 b), so Station Interface 501c does not transmit, Station Interface 501 c sets amessage-arrival-timer to approximately 2t_(AB) 107 a, and StationInterface 501 c awaits the next ATTS₅₀₀ message 300 a 2 arrival. Afterapproximate elapsed time interval 2t_(AB) 107 a, Station Interface 501 creceives messages 300 a 2 and 300 b 2. In the reverse ATTS₅₀₀ direction,message 300 b 2 is from Station Interface 501 c predecessor (StationInterface 501 b), so Station Interface 501 c transmits message 300 c 2,Station Interface 501 c sets a message-arrival-timer to approximately2t_(CD) 107 g, and Station Interface 501 c awaits the next ATTS₅₀₀message 300 d 2 arrival. After approximate elapsed time interval 2t_(CD)107 g, Station Interface 501 c receives message 300 d 2. Since message300 d 2 is from initial ATTS₅₀₀ defined Station Interface 501 d, IDMmessage Cycle 1 407 h and ATTS₅₀₀ reverse direction communications arecomplete. Station Interface 501 c reverses ATTS₅₀₀ to forward directionand receives message 300 d 3 commencing the next IDM message Cycle.

FIG. 5D illustrates IDM message Cycle 1 407 i ATTS₅₀₀ as detected andprocessed by Station Interface 501 b and may be described as follows. AtIDM message Cycle commencement, such as, but not limited to, IDM messageCycle 1 407 i, Station Interface 501 b is not the first ATTS₅₀₀ StationInterface 501 d, so Station Interface 501 b samples transmission media600 a signals awaiting ATTS₅₀₀ message 300 d 1 arrival. Afterapproximate time interval t_(DC) 107 l+t_(CB) 107 m, Station Interface501 b receives messages 300 d 1 and 300 c 1. In the forward ATTS₅₀₀direction, message 300 c 1 is from Station Interface 501 b's ATTS₅₀₀predecessor (Station Interface 501 c), so Station Interface 501 btransmits message 300 b 1, Station Interface 501 b sets amessage-arrival-timer to approximately 2t_(AB) 107 a, and StationInterface 501 b awaits the next ATTS₅₀₀ message 300 a 1 arrival. Afterapproximate elapsed time interval 2t_(AB) 107 a, Station Interface 501 breceives message 300 a 1. In the forward ATTS₅₀₀ direction message 300 a1 source Station Interface 501 a is not Station Interface 501 b'spredecessor (Station Interface 501 c), so Station Interface 501 b doesnot transmit, Station Interface 501 b sets a message-arrival-timer toapproximately 2t_(BE) 107 j, and Station Interface 501 b awaits the nextATTS₅₀₀ message 300 e 1 arrival. After approximate elapsed time interval2t_(BE) 107 j, Station Interface 501 b receives message 300 e 1. In theforward ATTS₅₀₀ direction message 300 e 1 source Station Interface 501 eis not Station Interface 501 b's predecessor (Station Interface 501 c),so Station Interface 501 b does not transmit, Station Interface 501 bsets a message-arrival-timer to approximately 2t_(EF) 107 k, and StationInterface 501 b awaits the next ATTS₅₀₀ message 300 f 1 arrival. Afterapproximate elapsed time interval 2t_(EF) 107 k, Station Interface 501 breceives message 300 f 1, which completes ATTS₅₀₀ forward directioncommunications.

Station Interface 501 b determines from its ATTS₅₀₀ copy that StationInterface 501 f is the last ATTS₅₀₀ ordered set member. StationInterface 501 b reverses ATTS₅₀₀ direction and Station Interface 501 breceives messages 300 f 2 and 300 e 2. In the reverse ATTS₅₀₀ direction,message 300 e 2 source Station Interface 501 e is not Station Interface501 b's predecessor (Station Interface 501 a), so Station Interface 501b does not transmit, Station Interface 501 b sets amessage-arrival-timer to approximately 2t_(AB) 107 a, and StationInterface 501 b awaits the next ATTS₅₀₀ message 300 a 2 arrival. Afterapproximate elapsed time interval 2t_(AB) 107 a, Station Interface 501 breceives message 300 a 2. In the reverse ATTS₅₀₀ direction, message 300a 2 is from Station Interface 501 b's predecessor (Station Interface 501a), so Station Interface 501 b transmits message 300 b 2, StationInterface 501 b sets a message-arrival-timer to approximately 2t_(BC)107 h, and Station Interface 501 b awaits the next ATTS₅₀₀ message 300 c2 arrival. After approximate elapsed time interval 2t_(BC) 107 h,Station Interface 501 b receives message 300 c 2. In the reverse ATTS₅₀₀direction, message 300 c 2 source Station Interface 501 c is not StationInterface 501 b's predecessor (Station Interface 501 a), so StationInterface 501 b does not transmit, Station Interface 501 b sets amessage-arrival-timer to approximately 2t_(CD) 107 g, and StationInterface 501 b awaits the next ATTS₅₀₀ message 300 d 2 arrival. Afterapproximate elapsed time interval 2t_(CD) 107 g, Station Interface 501 breceives message 300 d 2. Since message 300 d 2 is from the firstATTS₅₀₀ defined Station Interface 501 d, IDM message Cycle 1 407 i andATTS₅₀₀ reverse direction communications are complete. Station Interface501 b reverses ATTS₅₀₀ to forward direction and receives message 300 d 3commencing the next IDM message Cycle.

FIG. 5E illustrates IDM message Cycle 1 407 j ATTS₅₀₀ as detected andprocessed by Station Interface 501 a and may be described as follows. AtIDM message Cycle commencement, such as, but not limited to, IDM messageCycle 1 407 j, Station Interface 501 a is not the first ATTS₅₀₀ StationInterface 501 d, so Station Interface 501 a samples transmission media600 a signals awaiting ATTS₅₀₀ message 300 d 1. After approximate timeinterval t_(DC) 107 l+t_(CB) 107 m+t_(BA) 107 n, Station Interface 501 areceives messages 300 d 1, 300 c 1, and 300 b 1. In the forward ATTS₅₀₀direction, message 300 b 1 is from Station Interface 501 a's ATTS₅₀₀predecessor (Station Interface 501 b), so Station Interface 501 atransmits message 300 a 1, Station Interface 501 a sets amessage-arrival-timer to approximately 2t_(AB) 107 a+2t_(BE) 107 j, andStation Interface 501 a awaits the next ATTS₅₀₀ message 300 e 1 arrival.After approximate elapsed time interval 2t_(AB) 107 a+2t_(BE) 107 j,Station Interface 501 a receives message 300 e 1. In the forward ATTS₅₀₀direction message 300 e 1 source Station Interface 501 e is not StationInterface 501 a's predecessor (Station Interface 501 b), so StationInterface 501 a does not transmit, Station Interface 501 a sets amessage-arrival-timer to approximately 2t_(EF) 107 k, and StationInterface 501 a awaits the next ATTS₅₀₀ message 300 f 1 arrival. Afterapproximate elapsed time interval 2t_(EF) 107 k, Station Interface 501 areceives message 300 f 1, which completes ATTS₅₀₀ forward directioncommunications.

Station Interface 501 a determines from its ATTS₅₀₀ copy that StationInterface 501 f is the last ATTS₅₀₀ ordered set member. StationInterface 501 a reverses ATTS₅₀₀ direction and Station Interface 501 areceives messages 300 f 2 and 300 e 2. In the reverse ATTS₅₀₀ direction,message 300 e 2 is from Station Interface 501 a's predecessor (StationInterface 501 e), so Station Interface 501 a transmits message 300 a 2,Station Interface 501 a sets a message-arrival-timer to approximately2t_(AB) 107 a, and Station Interface 501 a awaits the next ATTS₅₀₀message 300 b 2 arrival. After approximate elapsed time interval 2t_(AB)107 a, Station Interface 501 a receives message 300 b 2. In the reverseATTS₅₀₀ direction, message 300 b 2 source Station Interface 501 b is notStation Interface 501 a's predecessor (Station Interface 501 e), soStation Interface 501 a does not transmit, Station Interface 501 a setsa message-arrival-timer to approximately 2t_(BC) 107 h, and StationInterface 501 a awaits the next ATTS₅₀₀ message 300 c 2 arrival. Afterapproximate elapsed time interval 2t_(BC) 107 h, Station Interface 501 areceives message 300 c 2. In the reverse ATTS₅₀₀ direction, message 300c 2 source Station Interface 501 c is not Station Interface 501 a'spredecessor (Station Interface 501 e), so Station Interface 501 a doesnot transmit, Station Interface 501 a sets a message-arrival-timer toapproximately 2t_(CD) 107 g, and Station Interface 501 a awaits the nextATTS₅₀₀ message 300 d 2 arrival. After approximate elapsed time interval2t_(CD) 107 g, Station Interface 501 a receives message 300 d 2. Sincemessage 300 d 2 is from the first ATTS₅₀₀ defined Station Interface 501d, IDM message Cycle 1 407 j and ATTS₅₀₀ reverse directioncommunications are complete. Station Interface 501 a reverses ATTS₅₀₀ toforward direction and receives message 300 d 3 to commence the next IDMmessage Cycle.

FIG. 5F illustrates IDM message Cycle 1 407 k ATTS₅₀₀ as detected andprocessed by Station Interface 501 e and may be described as follows. AtIDM message Cycle commencement, such as, but not limited to, IDM messageCycle 1 407 k, Station Interface 501 e is not the first ATTS₅₀₀ StationInterface 501 d, so Station Interface 501 e samples transmission media600 a signals awaiting ATTS₅₀₀ message 300 d 1 arrival. Afterapproximate elapsed time interval t_(DC) 107 l+t_(CB) 107 m+t_(BE) 107o, Station Interface 501 e receives messages 300 d 1, 300 c 1, and 300 b1. In the forward ATTS₅₀₀ direction message 300 b 1 source StationInterface 501 b is not Station Interface 501 e's predecessor (StationInterface 501 a), so Station Interface 501 e does not transmit, StationInterface 501 e sets a message-arrival-timer to approximately 2t_(AB)107 a, and Station Interface 501 e awaits the next ATTS₅₀₀ message 300 a1 arrival. After approximate elapsed time interval 2t_(AB) 107 a,Station Interface 501 e receives message 300 a 1. In the forward ATTS₅₀₀direction, message 300 a 1 is from Station Interface 501 e's ATTS₅₀₀predecessor (Station Interface 501 a), so Station Interface 501 etransmits message 300 e 1, Station Interface 501 e sets amessage-arrival-timer to approximately 2t_(EF) 107 k, and StationInterface 501 e awaits the next ATTS₅₀₀ message 300 f 1 arrival. Afterapproximate elapsed time interval 2t_(EF) 107 k, Station Interface 501 ereceives message 300 f 1, which completes ATTS₅₀₀ forward directioncommunications.

Station Interface 501 e determines from its ATTS₅₀₀ copy that StationInterface 501 f is the last ATTS₅₀₀ ordered set member. StationInterface 501 e reverses ATTS₅₀₀ direction and Station Interface 501 ereceives messages 300 f 2. In the reverse ATTS₅₀₀ direction, message 300f 2 is from Station Interface 501 e's predecessor (Station Interface 501f), so Station Interface 501 e transmits message 300 e 2, StationInterface 501 e sets a message-arrival-timer to approximately 2t_(AB)107 a+2t_(BE) 107 j, and Station Interface 501 e awaits the next ATTS₅₀₀message 300 a 2 arrival. After approximate elapsed time interval 2t_(AB)107 a+2t_(BE) 107 j, Station Interface 501 e receives messages 300 a 2and 300 b 2. In the reverse ATTS₅₀₀ direction, message 300 b 2 sourceStation Interface 501 b is not Station Interface 501 e's predecessor(Station Interface 501 f), so Station Interface 501 e does not transmit,Station Interface 501 e sets a message-arrival-timer to approximately2t_(BC) 107 h, and Station Interface 501 e awaits the next ATTS₅₀₀message 300 c 2 arrival. After approximate elapsed time interval 2t_(BC)107 h, Station Interface 501 e receives messages message 300 c 2. In thereverse ATTS₅₀₀ direction, message 300 c 2 source Station Interface 501c is not Station Interface 501 e's predecessor (Station Interface 501f), so Station Interface 501 e does not transmit, Station Interface 501e sets a message-arrival-timer to approximately 2t_(CD) 107 g, andStation Interface 501 e awaits the next ATTS₅₀₀ message 300 d 2 arrival.After approximate elapsed time interval 2t_(CD) 107 g, Station Interface501 e receives messages message 300 d 2. Since message 300 d 2 is fromthe first ATTS₅₀₀ defined Station Interface 501 d, IDM message Cycle 1407 k and ATTS₅₀₀ reverse direction communications are complete. StationInterface 501 a reverses ATTS₅₀₀ to forward direction and receivesmessage 300 d 3 commencing the next IDM message Cycle.

FIG. 5G illustrates IDM message Cycle 1 4071 ATTS₅₀₀ as detected andprocessed by Station Interface 501 f and may be described as follows. AtIDM message Cycle commencement, such as, but not limited to, IDM messageCycle 1 4071, Station Interface 501 f is not the first ATTS₅₀₀ StationInterface 501 d, so Station Interface 501 f samples transmission media600 a signals awaits the next ATTS₅₀₀ message 300 d 1 arrival. Afterapproximate elapsed time interval t_(DC) 107 l+t_(CB) 107 m+t_(BE) 107o+t_(EF) 107 p, Station Interface 501 f receives messages 300 d 1, 300 c1, and 300 b 1. In the forward ATTS₅₀₀ direction message 300 b 1 sourceStation Interface 501 b is not Station Interface 501 f's predecessor(Station Interface 501 e), so Station Interface 501 f does not transmit,Station Interface 501 f sets a message-arrival-timer to approximately2t_(AB) 107 a, and Station Interface 501 f awaits the next ATTS₅₀₀message 300 a 1 arrival. After elapsed time interval 2t_(AB) 107 a,Station Interface 501 f receives messages 300 a 1 and 300 e 1. In theforward ATTS₅₀₀ direction, message 300 e 1 is from Station Interface 501f's ATTS₅₀₀ predecessor (Station Interface 501 e), so Station Interface501 f transmits message 300 f 1, which ATTS₅₀₀ forward directioncommunications.

Station Interface 501 f determines from its ATTS₅₀₀ copy that it is thelast ATTS₅₀₀ ordered set member. Station Interface 501 f reversesATTS₅₀₀ direction and Station Interface 501 f transmits message 300 f 2,Station Interface 501 f sets a message-arrival-timer to approximately2t_(EF) 107 k, and Station Interface 501 f awaits the next ATTS₅₀₀message 300 e 2 arrival. After approximate elapsed time interval 2t_(EF)107 k, Station Interface 501 f receives message 300 e 2. In the reverseATTS₅₀₀ direction, as the last ATTS₅₀₀ ordered set member, StationInterface 501 f does not have a predecessor, so Station Interface 501 fdoes not transmit, Station Interface 501 f sets a message-arrival-timerto approximately 2t_(AB) 107 a+2t_(BE) 107 j, and Station Interface 501c awaits the next ATTS₅₀₀ message 300 a 2 arrival. After elapsed timeinterval 2t_(AB) 107 a+2t_(BE) 107 j, Station Interface 501 f receivesmessages 300 a 2 and 300 b 2. In the reverse ATTS₅₀₀ direction StationInterface 501 f does not have a predecessor, so Station Interface 501 fdoes not transmit, Station Interface 501 f sets a message-arrival-timerto approximately 2t_(BC) 107 h, and Station Interface 501 c awaits thenext ATTS₅₀₀ message 300 c 2 arrival. After elapsed time interval2t_(BC) 107 h, Station Interface 501 f receives message 300 c 2. In thereverse ATTS₅₀₀ direction Station Interface 501 f does not have apredecessor, so Station Interface 501 f does not transmit, StationInterface 501 f sets a message-arrival-timer to approximately 2t_(BC)107 g, and Station Interface 501 c awaits the next ATTS₅₀₀ message 300 d2 arrival. After elapsed time interval 2t_(CD) 107 g, Station Interface501 c receives message 300 d 2. Since message 300 d 2 is from initialATTS₅₀₀ defined Station Interface 501 d, IDM message Cycle 1 4071 andATTS₅₀₀ reverse direction communications are complete. Station Interface501 f reverses ATTS₅₀₀ to forward direction and receives message 300 d 3commencing the next IDM message Cycle.

As the Station Interface transmits only in accordance with the ATTS,elimination of collisions of signals transmitted by non-collocatedtransmitters has been achieved. Additionally, elimination of collisionsobviates the need for arbitration. Also, any existing device that isinvolved with collision detection and management and/or arbitration willoperate more efficiently and at high throughput when connected to aBSTTS network, because these activities are no longer are required tooperate and the bandwidth lost from their operation is available forpayload transmission by other stations.

Although use of the ATTS eliminates collisions, to achieve maximumefficiency for any collection of stations that establish communicationamong members of the collection the ATTS should be computed as anordered set with MPT. In a simple arrangement of stations, the stationorder would preferably mimic the order in which an energy transmissionwould pass each of the stations. For example, referring briefly to FIG.1, it is readily seen that, if station 101 a transmits a message, theenergy will propagate outward and pass stations 101 b, 101 c, 101 d and101 e, in turn. Therefore, an ATTS having the sequence 101 a, 101 d, 101b, 101 e, 101 c would have significantly longer and cumulativepropagation times than an ATTS have the sequence 101 a, 101 b, 101 c,101 d, 101 e because the station order is not in the order in which theenergy would naturally propagate from one station to the other stations.In practice, however, with more complex station positioning, withstations moving, and/or with branching, this simple analogy might notachieve the optimal results. For example, referring to FIG. 8, theoptimal sequence is not immediately apparent. Further, there may bereasons to use a sub-optimal ATTS. For example, a sub-optimal ATTS mightbe used where the stations are not able to process the data as quicklyas it might arrive and therefore need the additional propagation delayin order to process one round of data before another round of dataarrives. Another reason is that, as explained herein, the time requiredto compute the optimal ATTS might be excessive so a sub-optimal, orapproximate, ATTS is preferably used to begin communications and thenthe ATTS is continually and incrementally adjusted to achieve optimum ornear-optimum information transmission.

In the examples above, a complete IDM Message Cycle permitting allactive stations to exchange data with all other active stations hastaken place in the length of time to transmit the messages, plus onlythe accumulated physical cost of the accumulated transmissionpropagation delay along the ATTS. The maximum bandwidth utilization canbe achieved if and only if the accumulated transmission propagationdelay along the ATTS is minimized. Therefore, the ATTS must be realizedwithin the practical constraints of a real network where stations arecontinually being added and/or removed and/or are in motion. U.S. Pat.No. 4,935,877 to Koza, incorporated herein by reference, teaches thatthe number of possible alternative transmission order sequences is equalto the factorial of the number of stations (n!). It will therefore beappreciated that it is time prohibitive for even the fastest computersto attempt to solve this problem for the exact minimum propagation timefor even a relatively small number of stations. For example, Koza showsthat, for only fourteen stations, there are 87,178,291,200 (14!)possible computations needed to determine the optimum transmission ordersequence and, for example, if each of the possible routes could becomputed at the rate of one transmission order sequence per microsecond,then it would take approximately twenty-four hours to compute all thepossible transmission order sequences to determine the minimumpropagation time. In most networks this would be an unacceptable delayin starting up, and the joinder, exiting, or failure of even a singlestation might require restarting the computation process. This is evenless acceptable in a network with mobile stations, where stations aretypically joining and leaving at a rapid rate. Therefore, an exactdetermination of the ATTS with MPT for large number of stations is not apractical solution. One embodiment provides for a compromise betweendetermining the exact MPT and the computational time required. Thisprovides an ATTS that is a good approximation to MPT for large numbersof mobile and/or fixed stations.

In one embodiment, for any set of stations which establish communicationamong members of the set, the approximate ATTS with MPT is computed asan estimate of the TSP solution for all of the stations. Thetransmission path length as the ATTS connects all the stations istherefore minimized, and the maximum possible bandwidth utilization isapproached. To facilitate this computation, during the course of anormal IDM cycle, each Station Interface computes the number of clockintervals that have elapsed since the IDM Message Cycle started, andrecords that time as part of the message header 313. This enables eachStation Interface to compute the propagation time to ATTS members,thereby providing information for non-interfering station addition.

FIGS. 7A and 7B illustrate propagation times and propagation timeequalities used in connection with the descriptions concerning network500. For network 500 all the possible transmission sequence combinations(6!=720) are computed in order to determine the exact ATTS controlledIDM Message Cycle that has the MPT, which is given byMPT=t_(DC)+t_(CB)+t_(BA)+t_(AB)+t_(BE)+t_(EF)+t_(FE)+t_(EB)+t_(BA)+t_(AB)+t_(BC)+t_(CD)=2(t_(DC)+t_(CB)+2t_(AB)+t_(BE)+t_(EF)).

The accumulated propagation time among the ATTS Station Interfacesmeasures the amount of network bandwidth that cannot readily berecovered or used. Therefore, rapidly computing the ATTS, configuringtransmissions in accordance with the ATTS, and operating branchednetworks in accordance with the ATTS maximizes network throughput. Usinganother network propagation organization may have a longer propagationtime and, therefore, lower throughput. Configuring and operatingcustomer networks using the ATTS therefore provides the best value forthe customer's network capital investment.

However, different ATTS's may give the same results. For example, fourdifferent ATTS's, named: ATTS₅₀₀, ATTS₅₀₁, ATTS₅₀₂, and ATTS₅₀₃ couldmanage network 500 normal IDM Message Cycles 407 g, 407 h, 407 l, 407 j,407 k and 4071 and provide the same total propagation time MPT routes.

The first equivalent network 500 ATTS is ATTS₅₀₀=<Station Interface 501d, Station Interface 501 c, Station Interface 501 b, Station Interface501 a, Station Interface 501 e, Station Interface 501 f> as discussedpreviously herein.

The second equivalent network 500 ATTS is ATTS₅₀₁=<Station Interface 501d, Station Interface 501 c, Station Interface 501 a, Station Interface501 b, Station Interface 501 e, Station Interface 501 f>. From theprevious discussions ATTS₅₀, forward direction transmissions and reversedirection transmissions may be determined.

The third equivalent network 500 ATTS is ATTS₅₀₂=<Station Interface 501f, Station Interface 501 e, Station Interface 501 ba, Station Interface501 a, Station Interface 501 c, Station Interface 501 d>. From theprevious discussions ATTS₅₀₁ forward direction transmissions and reversedirection transmissions may be determined.

The fourth equivalent network 500 ATTS is ATTS₅₀₃=<Station Interface 501f, Station Interface 501 e, Station Interface 501 a, Station Interface501 b, Station Interface 501 c, Station Interface 501 d>. From theprevious discussions ATTS₅₀₁ forward direction transmissions and reversedirection transmissions may be determined.

FIG. 8 is an illustration of a larger BSTTS network 800 with aplurality, e.g., twenty-eight, of ATTS₈₀₀ connected fixed and/or mobilestations 101 (101 a, 101 b, 101 b 2, 101 c, 101 c 2, 101 d, 101 d 1, 101d 3, 101 e, 101 e 1, 101 e 2, 101 e 3, 101 e 4, 101 e 6, 101 e 7, 101 e8, 101 f 1, 101 f 2, 101 f 4, 101 f 5, 101 f 6, 101 g, 101 g 1, 101 g 3,101 g 4, 101 h, 101 h 2, 101 h 3) and one station 101 x requesting tojoin ATTS₈₀₀. Preferably, the Station Interfaces 501 associated with thestations 101 actually perform the described computations so that stationresources are not consumed. Station Interfaces preferably interact withthe station to receive information and status from the station, totransmit information and status to the station, and possibly to receiveinstructions from the station. In practice, searching all possible ATTScombinations to find the minimum propagation path consumes computationresources in proportion to the factorial of the number (n!) of StationInterfaces involved. For the case of FIG. 8, an exhaustive search of allthe possible ATTS combinations requires the calculation and inspectionof (28!=304,888,344,611,714,000,000,000,000,000) combinations todetermine the ATTS₈₀₀ for network 800. If one ATTS₈₀₀ combination iscalculated every picosecond it still would take 96,573,625.8 centuriesto compute the ATTS₈₀₀ with MPT, clearly an unacceptable delay.Therefore, in order to achieve an ATTS with an approximate MPT, StationInterfaces are preferably organized hierarchically into clusters of sucha size that the exact minimum path across one cluster can be computed ina short amount of time. The computational capability of the StationInterfaces may limit the maximum size of one cluster to a small numberof stations (for example, but not limited to, eleven). For this smallnumber of Station Interfaces, the ATTS connects the Station Interfaceswith a route or path of MPT. For any larger number of StationInterfaces, piecing together the paths through each cluster develops anapproximation to the MPT route. The description of a cluster includesthe identity of each member, the order of their appearance within theATTS, and a vector of the distances between each Station Interface inthe cluster.

In one embodiment an estimated ATTS₈₀₀ is determined within a reasonabletime, “reasonable” being consistent with the motion of the mobilestations, the estimate being a good approximation to the ATTS₈₀₀ withMPT so as to be BSTTS network operationally useful.

While the ATTS is used to control the transmissions from StationInterfaces connected to BSTTS networks, the Station Interfacesthemselves are preferably organized hierarchically in clusters, as shownin FIG. 8. The maximum cluster size may be, for example, but not limitedto, eight, or to some other size which allows for computation in areasonable time commensurate with the computational speed and abilitiesof the devices. It is possible to perform an exhaustive search of allpossible ATTS combinations (8!=40,320) and to compute, for thenon-limiting maximum cluster size of eight, the exact ATTS₈₀₀. Themaximum cluster size, however, is an implementation detail and isdependent upon the computational capabilities of the Station Interface,and therefore some maximum number of stations in a cluster shouldpreferably be established. In one embodiment a maximum cluster sizeconsistent with the computational capability of the Station Interfacesis used to compute the exact ATTS for that cluster which forms part ofthe BSTTS network.

In the example shown in FIG. 8 the primary cluster is preferablycomposed of stations 101 a, 101 b, 101 c 101 d, 101 e, 101 f, 101 g, and101 h; chosen merely because these eight stations first joined theoperating BSTTS network 800. The primary clusters transmit according tothe exemplary ATTS₈₀₀=<station 101 a, station 101 b, station 101 cstation 101 d, station 101 e, station 101 f, station 101 g, station 101h>. Stations 101 b and 101 c host sub-clusters, each with one otherstation. Station 101 d's sub-cluster has three stations 101 d, 101 d 1,101 d 3. Station 101 e's sub-cluster is full with eight stations 101 e,101 e 1-e 4, 101 e 6-e 8. Stations 101 f, 101 g, and 101 h host clustersof six, four and three stations, respectively.

FIG. 8 illustrates the result of generating an exact ATTS₈₀₀ from ahierarchical cluster set. Optimal and exact paths exist for the primarycluster (FIG. 8 heavy line) and for each sub-cluster. For example, theATTS₈₀₀ is generated starting with the first station (101 a in thiscase) on the primary cluster's ATTS₈₀₁ and traverses that cluster andall sub-clusters to produce the ATTS_(101a)=<station 101 a>. This isthen repeated for the second BSTTS network 800 station 101 b to produceATTS_(101b)=<station 101 b, station 101 b 2> and then connectsATTS_(101b) to produce ATTS_(101ab)=<station 101 a, station 101 b,station 101 b 2>. This is then repeated for the remaining local ATTS's:ATTS_(101c)=<station 101 c 1, station 101 c>; ATTS_(101d)=<station 101 d1, station 101 d, station 101 d 3>; ATTS_(101e)=<station 101 e 1,station 101 e 2, station 101 e 3, station 101 e 4, station 101 e,station 101 e 6, station 101 e 7, station 101 e 8>; ATTS_(101f)=<station101 f 1, station 101 f 2, station 101 f, station 101 f 4, station 101 f5, station 101 f 6>; ATTS_(101g)=<station 101 g 1, station 101 g,station 101 g 3, station 101 g 4>; and ATTS_(101h)=<station 101 h,station 101 h 2, station 101 h 3>.

Once the local ATTS's are determined, the process is then repeated toconnect the local ATTS's together to form the final ATTS₈₀₀=<station 101a, station 101 b, station 101 b 2, station 101 c 1, station 101 c,station 101 d 1, station 101 d, station 101 d 3, station 101 e 1,station 101 e 2, station 101 e 3, station 101 e 4, station 101 e,station 101 e 6, station 101 e 7, station 101 e 8, station 101 f 1,station 101 f 2, station 101 f, station 101 f 4, station 101 f 5,station 101 f 6, station 101 g 1, station 101 g, station 101 g 3,station 101 g 4, station 101 h, station 101 h 2, station 101 h 3>.

When a new Station Interface joins an existing BSTTS network conductingIDM Message Cycle transmissions and receptions the responsibility forcomputing a new ATTS falls upon the Station Interface attempting to jointhe operating BSTTS network with minimal interference to the existingIDM Message Cycles of the established operating network. Conventionalrouters consume payload bandwidth, use up large amounts of memoryresources, and expend significant computational resources. In oneembodiment, at time intervals established at system initialization,and/or adjustable automatically by the Station Interfaces usingfeed-forward and/or feed-back control loops and/or by the systemadministrator, one Station Interface on the ATTS will interrupt the IDMMessage Cycle long enough to transmit a special pause message(invitation-to-join message) and then wait for one network propagationdiameter (which may be an initialization parameter) for new StationInterfaces to respond. Being a relatively rare event, this joining delaytime has almost no effect on the available bandwidth. Contrast theoccasional insertion of this joining delay with implementationsdisclosed in U.S. Pat. No. 5,434,861 to Pritty et al.; and U.S.Published Application US2002/0101874A1 to Whittaker et al., where thedelay is imposed at the delivery of every message or message cycle. If anew Station Interface responds with a request to join the BSTTS network,the new Station Interface is provided with the identity of one of theprimary cluster nodes, and the joining process by the new StationInterface begins. Otherwise the established ATTS continues operation.

The joining process consists of three stages: finding a cluster withspace available, computing a new and optimal ATTS through that clusterincluding the new station, and assembling the new ATTS.

The first stage is a simple message exchange with one of the ATTSdefined Station Interfaces, followed by a process of observing theexisting IDM Message Cycle. This first stage is repeated recursivelywith almost no visible effect on the existing IDM Message Cycles until acluster is found with space for the new Station Interface.

Once a cluster is found, in the second stage, the Station Interface forthe new joining station computes a new, optimal ATTS through thatcluster. As a thorough search for the best path through even a smallnumber stations can consume a significant amount of computing time theexisting ATTS Station Interfaces are preferably allowed to continuetheir normal IDM Message Cycles until this computation is complete. Whenthat computation completes, a new cluster configuration is delivered tothe members of original cluster.

The third stage is actually a normal data cycle wherein the new StationInterface records the current ATTS, and then the new Station Interfacemerges into the existing ATTS the path through the new cluster to createan updated ATTS reflecting the presence and position of the new StationInterface. The joining Station Interface broadcasts this new ATTS to allStation Interfaces and the next IDM Message Cycle automatically operateswith the new ATTS.

Still referring to FIG. 8, assume now that a new station 101 x wishes tojoin the BSTTS network 800 and therefore observes BSTTS network 800operations and awaits a pause message. The pause message indicates thatit is safe for station 101× to transmit without causing interferencewith existing message traffic of the operating ATTS₈₀₀ network. Thisopportunity occurs periodically, at a time interval which may be set,but is not limited to being set, administratively for a specific BSTTSnetwork in one embodiment or, in another embodiment, this time intervalis adaptively determined for the BSTTS network. In one embodiment, whenthe pause interval occurs, one of the defined ATTS₈₀₀ stations, uponreceiving authority to transmit, sends a pause message instead of itsdata message. In another embodiment, all stations know that a pauseinterval will occur following the current IDM Message Cycle and so theystop transmitting, without any significant loss of bandwidth, to send apause message instead of a data message. The station sending the pausemessage could be any of the stations and determined by any desiredcriteria; for example: the last to send, the next to send, forwarddirection beginning (or ending) station, reverse direction beginning (orending) station, etc. For convenience of explanation and illustration,the station sending the pause message is referred to as the InvitingStation. The Inviting Station and all other stations then wait longenough for the pause message to reach the farthest feasible distance toa new station, and to receive an answer back. If there is no answerback, then the IDM Message Cycles continue until it is time for anotherpause message to be transmitted.

When the new station 101 x receives the pause message it immediatelyresponds with a request to join network 800. Station 101× then receivesfrom the Inviting Station a message establishing station 101 x's ownunique identity on the network 800 and the identity of one station inthe primary cluster, herein referred to for convenience as the ParentStation, which may or may not be the same as the Inviting Station. Thenew station 101 x times the round trip time between station 101× and theInviting Station and records this as the station 101 x propagation timeto the Inviting Station. This can be easily done because Station 101 xknows when it sent the message, the length of the message it sent, andwhen it received the reply message. Station 101× then sends to theParent Station a request to join the primary cluster. The Parent Stationsends a list of the cluster members and the propagation times betweenthe cluster members. The new station 101 x times the round trip timebetween station 101× and the Parent Station and records this as thestation 101 x propagation time to the Parent Station. Again, this can beeasily done because Station 101 x knows when it sent the message, thelength of the message it sent, and when it received the reply message.The Parent Station then resumes normal ATTS₈₀₀ IDM Message Cycles.Either the Inviting Station or the Parent Station also sends the currentATTS to the new station 101 x. The new station 101 x has the currentATTS information so it knows the order in which the various stations areto transmit, and knows the propagation times to the Inviting or ParentStation. The new station 101 x then observes one or more ATTS₈₀₀ IDMMessage cycles, computing and recording the propagation time to station101 x from each of the cluster member stations. Based upon thisinformation, station 101 x selects the closest primary station 101 e inthe example of FIG. 8.

When a Station Interface joins an operating network, that StationInterface determines the best cluster to join based on being closest inpropagation delay to that cluster and that cluster not being fullypopulated. The Station Interface attempting to join the operating ATTScomputes the path of MPT for that cluster, and then integrates thecomputed path into the existing ATTS to determine the new ATTS. When aStation Interface drops from the network, the Station Interfaces respondto its absence by removing it from the ATTS and continuing to operate.The other members of the dropped Station Interface's cluster also deletethe lost Station Interface information from their cluster specification.

After some suitable time interval, which in one embodiment is the nextpause interval, the Inviting Station sends a status message to station101 x asking if it is finished and waits for a response from station 101x. In response to this status message request, station 101 x may takeone of several actions, including, but not limited to, the following.

If the cluster under consideration is not full, station 101 x computes anew, optimal path through that cluster, including its own location, andawaits another status request.

If the current cluster under consideration is full, the station 101 xdeclares that the closest station in the current cluster is its newParent Station, sends that closest station a message requesting itscluster members, and awaits the response from that closest station. Uponreceiving that response, station 101 x begins analysis of the contentsof that cluster. As above, if the cluster under consideration is notfull, station 101 x computes a new, optimal path through that cluster,including its own location, and awaits another status request.

In either case, the joining station 101 x responds to the InvitingStation even if it is busy computing. If any status request messagearrives before station 101 x computation is finished, station 101 xreplies with a busy status message. Each of these status request messageexchanges occurs between multiples of complete IDM Message cycles withnegligible BSTTS network 800 available bandwidth impacts. That is, thestations already in the network do not wait for the new station 101 x tocomplete its calculations but, instead, carry on as if new station 101 xdoes not exist until station 101 x has completed its calculations. Thus,only the new station 101 x suffers any delay while it is computingpropagation delay times and/or the new ATTS.

When station 101 x finishes computing the new ATTS through the cluster,it sends that new cluster ATTS to the Parent Station and to the otherStation Interfaces in that cluster, and a third stage is entered whereinstation 101 x integrates the new cluster that includes station 101 x'sidentity with the existing ATTS₈₀₀. The cluster architecture istherefore maintained because the joining Station Interface distributesthe cluster information to each and all of its members as it completesthe joining process.

For the example network 800 wherein station 101 x joins ATTS₈₀₀, the newATTS is defined to be: ATTS₈₁₀=<station 101 a, station 101 b, station101 b 2, station 101 c 1, station 101 c, station 101 d 1, station 101 d,station 101 d 3, station 101 e 1, station 101 e 2, station 101 x,station 101 e 3, station 101 e 4, station 101 e, station 101 e 6,station 101 e 7, station 101 e 8, station 101 f 1, station 101 f 2,station 101 f, station 101 f 4, station 101 f 5, station 101 f 6,station 101 g 1, station 101 g, station 101 g 3, station 101 g 4 station101 h, station 101 h 2, station 101 h 3>.

In one embodiment, when the next status query occurs, for example, atthe end of the multiple IDM Message cycle, station 101 x broadcastsATTS₈₁₀ to all stations. All the stations receive ATTS₈₁₀ and the nextIDM Message cycle operates using ATTS₈₁₀ instead ATTS₈₀₀.

Station 101 x preferably has performed the following computations:analyzed the primary cluster and determined that station role was theclosest member, analyzed the cluster hosted by station 101 e, found itto be full, and found station 101 e 2 to be the closest one to station101 x, composed a new cluster hosted by station 101 e 2 containingstation 101 e 2 and station 101 x, ATTS_(101e2)=<station 101 e 2,station 101 x>, and composed ATTS₈₁₀.

By placing the measurement and computational burden on the joiningStation Interface certain benefits are obtained. While the joiningStation Interface is computing the new ATTS, which new ATTS includes thejoining Station Interface, the operating BSTTS network StationInterfaces, that is, those which are already part of the network, do notdevote resources, such as, but not limited to, buffers, computationaleffort, and bandwidth to this task. Thus, except the necessary andsufficient initial dialog, there is virtually no interference with theoperating BSTTS network's IDM Message Cycles. The joining StationInterface has the job of measuring distances between Station Interfacesand, as the joining Station Interface is not yet operating as acomponent of the operating BSTTS network, the joining Station Interfacecan compute the new ATTS using the computational assets which willeventually be allocated for message management and data storage, thuslowering the cost of the Station Interface while maintaining the speedof the network even as a new Station Interface is joining.

Station Interfaces generally follow the behavior illustrated in FIGS.9-12. The operation of Station Interfaces is generally illustrated inthe state transition diagram of FIG. 9, and the message sequencediagrams of FIGS. 10-12.

FIG. 9 is an exemplary state transition diagram illustrating the variousstates of a Station Interface and generally shows the various modes orstates in which a Station Interface can exist, and identifies theconditions under which the Station Interface will change state.Preferably, these modes or states are executed by all of the StationInterfaces. The state transitions are preferably caused either by thearrival or departure of certain messages or by time elapsing withoutreceiving the expected response. After power up START 901, a StationInterface preferably begins in START_UP_FIND_PAUSE 903 state. TheStation Interface then proceeds to either stateSTART_UP_SEND_NEW_STN_MODE 925 as a new station after receiving thePause message to perform the new station computations, or to stateCLEAN_UP_SEND_PAUSE 915 as the original station of a network to host theprimary cluster, which may occur, for example, because of a time outcondition which indicates there are not any new stations wishing tojoin.

After either startup sequence, a Station Interface spends the bulk ofits time alternating between the central cycles. In the first centralcycle, a Station Interface moves from state NORMAL_SEND_DATA_MODE 905 tostate NORMAL_WAIT_FOR_FIRST_MODE 907 to stateNORMAL_WAIT_FOR_PARENT_MODE 911, and then to state NORMAL_SEND_DATA_MODE905. In the second central cycle, a Station Interface moves from stateNORMAL_SEND_DATA_MODE 905 to state NORMAL_WAIT_FOR_LAST_MODE 909 tostate NORMAL_WAIT_FOR_PARENT_MODE 911, and then to stateNORMAL_SEND_DATA_MODE 905.

The Station Interfaces that happen to be first and last on the ATTSspend the bulk of their time alternating between the first and secondcentral cycles with the addition of the state NORMAL_SEND_SECOND_MODE913 as illustrated in FIG. 9.

The Inviting Station uses the following join process: stateNORMAL_SEND_DATA_MODE 905 to state NORMAL_SEND_SECOND_MODE 913 to stateCLEAN_UP_SEND_PAUSE_MODE 915 to state CLEAN_UP_WAIT_AFTER_PAUSE_MODE 917to state CLEAN_UP_SEND CLUSTER 919 to state NORMAL_WAIT_FOR_STATUS_MODE923 to state NORMAL_SEND_QUERY_MODE 921 to stateNORMAL_WAIT_FOR_STATUS_MODE 923 to state NORMAL_SEND_SECOND_MODE 913. Bythis process the Inviting Station Interface has sent a pause message,allowed a time for a reply, sent the cluster and parent information tothe new station, and received the new cluster information and ATTS fromthe new station.

FIG. 9 also illustrates the sequence of states, beginning at state 925,followed by the new station as it computes the new ATTS and broadcaststhe new ATTS to all active Station Interfaces, and then joins the normalcycle at NORMAL_WAIT_FOR_PARENT_MODE 911.

FIGS. 10-12 are message sequence diagrams that show the details of themessage flow and the state changes when two, three and four StationInterfaces, respectively form or join a primary cluster. In FIGS. 10-12,the messages and their directions are identified in the center of eachfigure and the corresponding state transitions are annotated down themargins of each figure.

FIG. 10 shows the details of the message flow and the state changes whentwo Station Interfaces 101 a and 101 b form a primary cluster. StationInterface 101 a begins by listening for other transmitting StationInterfaces. However, as a cluster has not yet been formed, StationInterface 101 a times out and begins sending pause messages. StationInterface 101 b starts in the same way, that is, by listening for othertransmitting Station Interfaces. Before Station Interface 101 b timesout, however, Station Interface 101 b receives the pause messages fromStation Interface 101 a. Station Interface 101 b therefore begins thedialog with Station Interface 101 a to establish IDM Message Cyclecommunications and form the primary cluster. This simple caseillustrates the starting sequence uncluttered by any other messagetraffic. Note that Station Interface 101 b, as the joining StationInterface, has the job of computing delays.

FIG. 11 shows the details of the message flow and the state changes whena third Station Interface 101 c wishes to join the primary cluster. Inthis example it is presumed that Station Interfaces 101 a and 101 b,and/or some other Station Interfaces, have already formed the primarycluster. Station Interface 101 c begins by listening for othertransmitting Station Interfaces and detects the traffic from StationInterfaces 101 a and 101 b. It then, at the appropriate time, joins theoperating network. Notice that Station Interface 101 c proceeds throughthe same state transitions, as Station Interface 101 b in FIG. 10, andthat the original operating BSTTS network, Station Interface 101 a andStation Interface 101 b, are running the IDM Message Cycles with minorinterruption from Station Interface 101 c's dialog with StationInterface 101 a. Note that Station Interface 101 c, as the joiningStation Interface, has the job of computing delays and sending the newATTS.

FIG. 12 shows the details of the message flow and the state changes whena fourth Station Interface 101 d wishes to join the primary cluster. Inthis example it is presumed that Station Interfaces 101 a-c, and/or someother Station Interfaces, have already formed the primary cluster.Station Interface 101 d begins by listening for other transmittingStation Interfaces and detects the traffic from Station Interfaces 101a-c. It then, at the appropriate time, joins the operating network.Station Interface 101 d proceeds through the same state transitions asStation Interface 101 b in FIG. 10 and as Station Interface 101 c inFIG. 11, and that the original operating BSTTS network, StationInterface 101 a, Station Interface 101 b and Station Interface 101 c,are running IDM Message cycles with minor interruption from StationInterface 101 d's dialog with Station Interface 101 a. Note that StationInterface 101 d, as the joining Station Interface, has the job ofcomputing delays and sending the new ATTS.

A robust and functional network system, especially one involving mobilestations, must allow an active station to be dropped from the networkbut still leave the network operating normally, and with minimaldisruption. Removing a station that drops from the network whilemaintaining the integrity of the network involves two activities: theATTS is updated or repaired in order to maintain the flow of messages;and the cluster architecture is updated or repaired to facilitatesubsequent station joining.

Each Station Interface preferably separately maintains and updates itscopy of the ATTS by continually operating, in one embodiment, at leastone timer with two purposes or, in another embodiment, two or moretimers. When a message is received from the Station Interface's ATTSpredecessor, the value of that timer and the size of the messagereceived are used to compute the accumulated ATTS propagation time sincethe start of an IDM Message cycle. The Station Interface puts that valueinto the outgoing message header. The timer is, or the timers are, thenreset and begin measuring time again.

If the timer expires before a next message is received from the ATTSdefined Station Interface predecessor, that Station Interfacepredecessor is presumed to have dropped from the network so the StationInterface deletes the ATTS Station Interface predecessor from its localcopy of the ATTS and immediately sends its own data or status message.An allowance, of a predetermined amount of time, may be provided, ifdesired, so that small delays in reception caused by, for example, thestations moving farther apart do not result in the erroneous presumptionthat a station has dropped out. All the Station Interfaces check whichStation Interfaces have transmitted every IDM Message cycle, and removethose Station Interfaces that have not transmitted within the IDMMessage cycle from their ATTS. Therefore, the non-transmitting StationInterfaces are removed from all the ATTS copies across the networkwithin the IDM Message cycle. Should the dropped Station Interfacesubsequently need to rejoin the operating BSTTS network, that StationInterface goes through the normal Station Interface join process.Optionally, at the discretion of the network administrators, a StationInterface may be required to be reset, manually and/or automatically,before it can initiate a rejoining cycle and/or before it will beallowed to rejoin. This reduces adverse effects on the network caused byan erratic device if the problem can be resolved by resetting, e.g.,restarting, the device. The cluster architecture preferably is repairedafter the loss of a station.

All Station Interfaces, including those that are preparing to join theoperating network, monitor operating network traffic and each StationInterface is immediately aware of the loss of any and all stations thatdrop out of the operating network. The remaining Station Interfaces in acluster can determine whether one and/or more of their members aremissing, and need do nothing when none of their members is missing.

When a member is missing, the following actions occur. If the droppedStation Interface is not the host of another cluster then that StationInterface is simply removed from the cluster. If the dropped StationInterface is the host of another cluster then another member of thatcluster must assume the role of hosting that cluster. The best candidatefor this role is a member of that cluster which is currently not hostinganother cluster, i.e., a “leaf node” on the that cluster. A depth-firstsearch is therefore performed to find a leaf node in that clusterhierarchy, the leaf node is removed from its current cluster, and thenthe leaf node is installed as the host of the cluster which just lostits host Station Interface. In one embodiment, these actions areperformed by the Station Interface to which the dropped StationInterface was the predecessor Station Interface. In another embodiment,a Station Interface which can communicate with another member of thatcluster performs the actions.

BSTTS Station Interfaces therefore self-organize and self-manage theATTS, and can accurately set their message-arrival-timers. Themessage-arrival-timers permit BSTTS networks to operate more bandwidthefficiently than conventional networks when, for example, a BSTTSStation Interface drops from the BSTTS networks. Also, operating withthe self-organizing and self-managing ATTS provides inherent healthmonitoring of the BSTTS networks without the need for the expenditure ofadditional network resources.

An operating cluster preferably continually monitors the message trafficwith the goal of improving the optimality of the ATTS. This provides forthe continued, efficient operation of a network, especially one whichcontains mobile stations. Returning to the matter of solving the TSP,because of its computational complexity, solutions to the TSP for asignificant number of nodes are generated in two stages: an initialestimate of the solution; and a period of analysis attempting to improvethe solution by various techniques. In one embodiment, each StationInterface calculates its propagation time to its neighbors, andtherefore can easily determine the propagation time to all theirneighbors. From these data, it is therefore readily possible to performa local optimization that will re-order this small group of stations.Preferably, each Station Interface performs these calculations on acontinuous basis, or at least at regular intervals. Whenever such anoptimized re-ordering is then automatically determined, a new,re-ordered ATTS is distributed to all Station Interfaces when one of theStation Interfaces has the authority to transmit. In one embodiment,this is done when the Station Interface does not have any payload datato send. These calculations could also be done by a station rather thana Station Interface. As before, normal operation of the BSTTS networkresumes uninterrupted on the next IDM Message cycle.

The above procedure provides several benefits. First, by refining thequality of the ATTS, the network bandwidth available under normalcircumstances is continually improved. The results from the hierarchicalcluster TSP solution are most likely to be adversely affected at thetransition from one cluster to another, where long paths may be created.By locally analyzing this situation, the Station Interfaces are able toshorten the ATTS propagation time and thereby improve the availablebandwidth. Second, bandwidth availability is maintained even when some,or all, of the stations are in motion. Thus, unlike the prior art, thestations operating as disclosed herein can operate at near optimalefficiency even when all the stations are moving in three dimensions inany transmission media 600 that supports digital packet transmission. Aproblem generally unique to mobile stations, compared to a fixedstation, is that the propagation time may increase as the stations moveaway from the original configuration for which the ATTS was optimized.However, once the initial ATTS has been constructed, this activeself-assessment process continually adapts the approximate ATTS tocounter the effects of station mobility on the efficiency of bandwidthutilization. In one embodiment, this is performed thousands of times persecond, but still has little or no cost in bandwidth during normal IDMMessage Cycles.

In the refinement of the ATTS, close approximations to the optimal TSPsolution are computed for use to organize and to control networks with alarge numbers of stations; propagation time measurements induce minimalto no interference with the operation of the communicating network;network efficiency of the ATTS improves through continual refinements;and collisions are avoided during the joining process.

Communicating among a large number of stations on shared transmissionmedia 600 with the lowest lost network bandwidth requires acomputationally practical solution to the TSP. Exact solutions to theTSP are extremely computationally expensive, and can be achievedpractically using today's hardware, for example, for less than a dozenstations. Some approximate solutions apply only to linear networks.Others, using the classical approximation referred to as the MinimalSpanning Tree (MST), still require significant amounts of computationand memory, and are guaranteed to achieve a solution only within afactor of 2 of the optimal solution. In particular, the amount of memoryconsumed by the MST technique grows as N², and the computational load asgrows as N³, where N is the number of stations. These MSTcharacteristics, using today's hardware, make the limiting practicalupper bound of this algorithm application to somewhere around 200stations or less.

In one embodiment, an approximate ATTS is constructed and maintained inreal-time and the logic that computes the approximate TSP solution isimplemented in two parts: the logic for a Station Interface to join thenetwork and create a new approximate ATTS, and the logic for eachStation Interface to contribute to the maintenance of the existing ATTS.

A hierarchical clustering technique is used in one embodiment and canachieve, within 20%, the optimal TSP solution for over 10,000 stationswhile consuming minimal computation and memory resources. This providesfor practical implementation based upon available standard hardwareStation Interface implementations. This also results in no computationalload placed on the Stations or Station Interfaces already communicatingover the established network, provides minimum operating networkinterference, and provides for minimum communications bandwidthconsumption.

BSTTS networks are self-organizing, Self-Managed, and do not require anetwork administrator in that they can respond to, and recover from,conditions that cause one or more Station Interfaces to lose contactwith other Station Interfaces. In one embodiment, all Station Interfacesare compatible in behavior. As mentioned herein, in one technique forcomputing the approximate ATTS connectivity the Station Interfaces arearranged hierarchically in clusters. As with all hierarchies, there is aroot cluster from which the other clusters extend. This root cluster isreferred to as the Primary Cluster, which may be of any convenient sizethat is compatible with current hardware Station Interface computationalcapabilities. Membership in this Primary Cluster is accomplished merelyby being among the first Station Interfaces to join the network. In oneembodiment, significant separation from other Station Interfaces may berequired and, otherwise, membership in the Primary Cluster is denied bymembership in a non-Primary Cluster is provided. This hierarchy iscompletely Self-Managed. For example, in one embodiment, if one of thePrimary Cluster Station Interfaces drops from the network, the nextStation Interface to join is added to the Primary Cluster or a StationInterface in a non-Primary Cluster may become a member of the PrimaryCluster.

Subsequently, any station joining the BSTTS network finds its locationin the hierarchy by first communicating with one of the Primary ClusterStation Interfaces. That Station Interface provides the joining StationInterface with the identity of its cluster members and a table of itsdistances and/or time from the other members. The logic in the joiningStation Interface then computes its distance from each Primary ClusterStation Interface and chooses the closest. As this chosen StationInterface may itself be the host of another cluster, the joining StationInterface sends a message asking to join the cluster of the chosenStation Interface. If space in that cluster is available permission maybe granted. If space in that cluster is not available, the process isrepeated until a cluster is found which has an available space for thenew Station Interface.

The joining Station Interface then adds itself to that cluster andcomputes the path connecting the Station Interfaces of this cluster,including itself in the cluster. Next, the joining Station Interface, inorder to form the new ATTS, determines the proper place to splice intothe cluster, deletes all the old nodes in this cluster from the currentATTS, then inserts the new cluster into the ATTS, and then computes anew ATTS. This new ATTS is distributed to all the Station Interfaces,and communications including the joining station resume at the beginningof the next IDM Message Cycle.

In one embodiment, the non-interfering measurement of propagation timesbetween stations supports the logic for a joining station to connect thenetwork with minimal interference with existing message traffic, andsupports the continual process of maintaining optimal performanceregardless of whether stations are moving as the TSP solution, accordingto one embodiment, is an approximation, and the Station Interfacescontinually evaluate and improve the ATTS path length.

During every normal IDM Message Cycle, each Station Interface computesthe propagation delay to ATTS members by timing the round-trippropagation time. When each IDM Message Cycle begins, the first ATTSstation inserts into its message header a propagation time of zero. Asthe IDM Message Cycle proceeds, each station includes in its headermessage the cumulative propagation time since that IDM Message Cycle.

The propagation time from the joining station to any given station of acluster can then be determined. During the initial message exchange withthe Inviting Station Interface, the joining Station Interface measuresthe round-trip propagation time to the Inviting Station Interface. Amessage received from any station contains the accumulated propagationtime from the beginning of the IDM Message Cycle. The propagation timefrom the joining station to the source of that message is computed asthe accumulated propagation time minus its propagation time from theInviting Station Interface as measured above.

Classical TSP algorithms for large systems typically begin with a goodapproximation to the solution and then refine that solution, continuallymoving it towards the absolute optimum. These refinement techniques comein two forms: macro analyses including Monte Carlo style randomperturbations of the solution in the hope of escaping a local minimum,and local optimizations removing obvious inefficiencies, such as fourstations connected in an “X” pattern rather than a box.

The results of the clustering algorithm may not necessarily be globallyoptimal due to the assembly of the paths connecting cluster local paths.An ATTS may be produced with long reaches between cluster ends. Oneembodiment improves the ATTS dynamically by removing “X” patterns.Referring to FIG. 8, each station, for example station 101 c, examinesthe propagation times to its two previous ATTS neighbors on the ATTS,station 101 a and station 101 b. If station 101 c's propagation time tostation 101 a is less than its propagation time to station 101 b, thenan “X” pattern connection has accidentally formed. Station 101 crecommends that station 101 a and station 101 b be exchanged within theATTS. This recommendation is propagated to all stations to maintainintegrity of the ATTS copies.

During normal network IDM Message Cycles, the authority to transmit isdeterministic and no collisions are possible. However, a situation mayoccur when multiple stations simultaneously attempt the initial dialogto join the BSTTS network, and happen to be close to the same distancefrom the ATTS Inviting Station. In this case, both joining stations willtransmit and a collision may occur, corrupting both messages from thenew stations. Many broadcast media do not permit collision sensing.However, if a collision occurs, the Inviting Station will reject thecorrupted messages and not respond to them. Each new station willdetermine from the lack of response from the Inviting Station that itsmessage was lost. As this is only occurs during the joining process, andthe only affected stations are the ones not already connected to theoperating BSTTS network, there is no significant cost to using larger,random, back-off times for the joining stations to escape furthersimultaneous join attempts. If both joining stations transmitted theirjoin request, but a collision did not occur, then the network respondsto the first request received and ignores subsequent requests, therebytriggering the same back-off response in the remaining station(s) as ifa collision had occurred.

FIGS. 13A and 13B are block diagrams illustrating the functionalelements of an exemplary Station Interface 501. For clarity ofillustration, the Station Interface 501 is shown and described as areceive-functionality element 1300 and a transmit-functionality element1350.

FIG. 13A is a block diagram illustrating the receive-functionalityelement 1300 of an exemplary Station Interface 501. Station Interface501 receives messages 300 (300 a 8, 300 b 7, 300 n 1, 300 a 9, 300 n 2,300 c 3, 300 d 4, 300 e 3, 300 f 3, and 300 g 1) from one or more of thesame or different transmission media 600 m, 600 n and 600 o through oneor more receive processing logic units (“Receive From TransmissionMedia”) 1304 a, 1304 b, and 1304 n. Receive processing logic units 1304a, 1304 b, and 1304 n send the messages 300, via one or more of the sameor different transmission media 600 k 4, 600 k 9, and 600 k 14, to oneor more message buffers 1302 a, 1302 b, and 1302 n units. Messagebuffers 1302 a, 1302 b, and 1302 n temporarily store the messages 300and forward the messages 300 via one or more of the same or differenttransmission media 600 k 2 600 k 7, and 600 k 12 to one or more transmitprocessing logic units (“Send To Station Transmission Media”) 1301 a,1301 b, and 1301 n. The transmit processing logic units 1301 a, 1301 b,and 1301 n units deliver the messages 300 to one or more stations ofarbitrary complexity 101 a, 101 b, and 101 n, via one or more of thesame or different transmission media 600 g, 600 h, 600 l, 600 j, 600 p,600 q, 600 r, 600 s, and 600 u. Control of the Station Interface 1300 isimplemented with one, two, or a plurality of BSTTS Message Control andTimer units 1303 a, 1303 b, and 1303 n transmitting and receivingcontrol signals and transmitting and receiving control information viaone or more serial and/or parallel, same or different, transmissionmedia 600 k 1, 600 k 3, 600 k 5, 600 k 6, 600 k 8, 600 k 10, 600 k 11,600 k 13, and 600 k 15. Although the Station Interface 501 is shown ashaving a receive-functionality element 1300 which has a plurality oftransmit processing logic units 1301, message buffers 1302, MessageControl and Timers 1303, and receive processing logic units 1304, and asbeing connected to a plurality of Stations 101, this is not arequirement and a Station Interface 501 may be dedicated to a singlestation 101 and only have a single receive-functionality element 1300, asingle transmit processing logic unit 1301, a single message buffer1302, a single Message Control and Timer 1303, and a single receiveprocessing logic unit 1304.

FIG. 13B is a block diagram illustrating the transmit-functionalityelement 1350 of an exemplary embodiment Station Interface 501. StationInterface 501 receives, from one or more stations 101 a, 101 b, and 101n, via one or more of the same or different transmission media 600 v,600 w, 600 x, 600 y, 600 z, 600 aa, 600 ab, 600 ac, and 600 ad, messages300 (300 a 10, 300 a 11, 300 a 12, 300 b 8, 300 b 9, 300 b 10, 300 n 3,300 n 4, 300 n 5, 300 n 6, 300 n 7, and 300 n 8) by the use of one ormore receive processing logic units (“Receive From Station TransmissionMedia”) 1351 a, 1351 b, and 1351 n. Receive processing logic units 1351a, 1351 b, and 1351 n route messages 300 by way of one or more of thesame or different transmission media 600 t 2, 600 t 7, and 600 t 12 toone or more message buffers 1352 a, 1352 b, and 1352 n. Message buffers11352 a, 1352 b, and 1352 n temporarily store messages 300 and thenforward messages 300 via one or more of the same or differenttransmission media 600 t 4, 600 t 9, and 600 t 14 to one or moretransmit processing logic units (“Transmit To Transmission Media”) 1354a, 1354 b, and 1343 n. Transmit processing logic units 1354 a, 1354 b,and 1343 n deliver messages 300 to one or more of the same or differenttransmission media 600 ae, 600 af, and 600 ag. Control of the StationInterface 1350 is implemented with one or more BSTTS Message Control andTimer Units 1353 a, 1353 b, and 1353 n, which transmit and receivecontrol signals and transmitting and receiving control information viaone or more of serial and/or parallel, same or different, transmissionmedia 600 t 1, 600 t 3, 600 t 5, 600 t 6, 600 t 8, 600 t 10, 600 t 11,600 t 13, and 600 t 15. Although the Station Interface 501 is shown ashaving a transmit-functionality element 1350 which has a plurality ofreceive processing logic units 1351, message buffers 1352, MessageControl and Timers 1353, and transmit processing logic units 1354, andas being connected to a plurality of Stations 101, this is not arequirement and a Station Interface 501 may be dedicated to a singlestation 101 and only have a single transmit-functionality element 1350,a single receive processing logic unit 1351, a single message buffer1352, a single Message Control and Timer unit 1353, and a singletransmit processing logic unit 1354.

It will be appreciated that many of the components shown therein may beshared. For example, units 1301 and 1351 may be part of a singleinterface with a Station 101. Likewise, units 1304 and 1354 may be partof a single interface with a communications media 600. In addition, thecontrol and timer units 1303 and 1353 may be a single unit whichcontrols both transmit and receive operations. And, in addition, buffers1302 and 1352 may be part of the same memory unit, or even part of thecontrol and timer unit 1303, 1353.

Also, a single unit 1301 a may be used, for example, to demultiplexslower signals to two or more stations 101 a, 101 b . . . and 101 n froma Station Interface 1300. Further, a single unit 1351 a unit maymultiplex signals from two or more stations 101 a, 101 b . . . and 101 nto a Station Interface 1350.

The performance of networks constructed and operated as described hereincan be easily ascertained and documented, with minimal to no performancepenalty to network operations. In one embodiment, by listening to themessages traveling on the transmission media, any and all of the StationInterfaces can gather network statistics and create an event logdocumenting network performance. In another embodiment, a network mayhave dedicated Station Interfaces that gather network statistics andcreate an event log documenting the performance of the network. In yetanother embodiment, another system monitors the communications on thenetwork and records the associated performance, for example forperforming and gathering on-line test results, diagnostic information,and prognostic information.

If one considers the ATTS to be a list, the reverse ATTS may be aseparate list, or may be the same list but executed in the oppositedirection.

Also, a station may switch from using a forward ATTS to a reverse ATTSat any point which is convenient and which does not introduce error oruncertainty. For example, when a station is implementing the forwardATTS the station may switch to implementing the reverse ATTS once thelast station listed in the forward ATTS has transmitted, may switch toimplementing the reverse ATTS once its successor or one or more othersubsequent stations in the forward ATTS has or have transmitted, mayswitch to implementing the reverse ATTS once it detects one or moreother stations transmitting in the order specified in the reverse ATTS,may switch to implementing the reverse ATTS once it has transmitted,especially if it is at an endpoint (the first or last station) on theATTS, etc.

Generally, a station monitors the transmissions of other stations andwill transmit a message when it has received a message from itsimmediate predecessor station, giving due consideration to whether theforward ATTS or the reverse ATTS is in effect. Also, giving dueconsideration to whether the forward ATTS or the reverse ATTS is ineffect, a station will transmit a message when it has detected thefailure to timely receive a message from its immediate predecessorstation.

As a station knows the order of transmission from the ATTS or thereverse ATTS, and has either determined or been provided the propagationtime with respect to each other station, or at least some of the otherstations, preferably at least two or three predecessor stations aslisted in the ATTS or the reverse ATTS as appropriate, a station willknow, once a message has been received from one predecessor station, howlong the delay should be before a message from a next predecessorstation (next in the ATTS) is received.

For example, if there a five stations, A-E (not shown), and station Ereceives a message from station A, station E will know when it shouldbegin receiving a message from station B and, once station E hasreceived the message from station B, station E will know when it shouldbegin receiving a message from station C and, once station E hasreceived the message from station C, station E will know when it shouldbegin receiving a message from station D. Therefore, if station E doesnot begin receiving a message from station D by that time, or shortlythereafter, for example, a nominal delay time so as to compensate forprocessing time, movement of the stations, etc., then station E willdetermine that station D has dropped out, and station E will begintransmitting. The other stations will also act accordingly, based upontheir own propagation delay time calculations and nominal times. Once astation has determined that another station has dropped out it removesthat station from the ATTS.

Optionally, if station E receives a message from station B, but does notreceive a message from station C, station E will determine that stationC has dropped out. Station E will expect to receive a message from itspredecessor, station D, within two nominal delay times, one nominaldelay time for station D to determine that station C has dropped out,and one nominal delay time for the expected transmission from station D.If station E does not receive a message from station D within this timethen station E will determine that station D has also dropped out. Theother stations will also act accordingly, based upon their ownpropagation delay time calculations and nominal times.

From the above, many of the benefits of, and features provided by, thepresent invention will now be apparent. Some examples of those benefitsand features are given below.

Systems containing one, two or a plurality of common paths supplied byone, two or a plurality of joining paths, for example, but not limitedto, home networks, industrial process control networks, server accessmanagement, storage device and systems management, vehicular trafficmanagement, air traffic management, rail-based traffic management,manufacturing work flow management, logistics flow management, transportvehicle packing, and transport vehicle load control can be implementedusing, and benefit from, the teachings herein.

BSTTS networks might be linear, and/or branched, and/or moving in4-dimensional space-time.

Station Interfaces can be automatically added to and/or deleted from theBSTTS network.

The BSTTS network stations may be as simple as remote sensors supplyinginformation to other users, digital radios carried by vehicles, and/orindividuals, and/or stationary, gateways to other networks, and/orstations of arbitrary complexity.

BSTTS networks are self organizing and Self-Managed and humaninteraction is not required to construct and to maintain network optimalperformance. Therefore, Self-Managed-Efficient ad hoc networks andSelf-Managed-Efficient ad hoc networks of networks are possible and canbe dynamically organized and managed. A network may consist of a fewStation Interfaces to tens-of-thousands of collocated and/or distributedStation Interfaces.

The bandwidth and the throughput available to all Station Interfaces aremaximized by ensuring that, at any given time, only one StationInterfaces has the authority to transmit.

Station Interfaces are self-aware in that each active Station Interfacerecords information such as, but not limited to, the activities of otherStation Interfaces and the relative propagation times to StationInterfaces. Because of this self-awareness, the Station Interfaces donot require continual attention from a network administrator because,for example, network status is always available at and known to everyStation Interface.

There is little or no need for collision detection, and/or collisionmanagement, and/or arbitration because the ATTS used in the BSTTSnetwork prevents transmission media message collisions.

BSTTS networks operate seamlessly over a wide range of network diametersand across communications media boundaries.

BSTTS networks provide for efficient transmission of a wide range ofmessage sizes and message structures.

BSTTS networks permit transmission and message reception acknowledgementto and from to all the BSTTS network Station Interfaces in a single IDMMessage Cycle.

BSTTS networks permit: broadcasting to all Station Interfaces, multicastto any subset of the Station Interfaces, and/or one or morepoint-to-point transmissions between Station Interfaces in a single IDMMessage Cycle.

BSTTS network performance, with respect to bandwidth, scales essentiallylinearly with message size and number of users.

BSTTS networks significantly increases the throughput available to eachuser or station connected via Station Interfaces to one, two or aplurality of network media physical layers.

The BSTTS methods and devices can be utilized in any number of differentnetwork physical and topological configurations.

One, two, a plurality, or all Station Interfaces on a composed BSTTSnetwork may transmit within the time span of a network diameter.

BSTTS network performance is a priori deterministic and its performancecan easily be determined before the network is built.

One, two or a plurality of stations of arbitrary complexity can beconnected to one, two or a plurality of the same or differenttransmission media 600 by way of one, two or a plurality of StationInterfaces.

Many physical implementations are possible. Implementation may be, forexample, by processing logic that may comprise hardware (such as, butnot limited to, dedicated logic circuitry, programmable logic circuitryand firmware), software (such as, but not limited to, instructions runon a general purpose computer system or a dedicated machine), orcombinations of all types of processing logic. Instructions (also knownas computer programming instructions, computer programs, software,firmware, or reconfigurable logic circuitry) may be stored in the memoryand logic circuitry of the Station Interfaces and/or the Station. In oneembodiment Station Interface instructions may be received via thetransmission media 600 connected to Station Interfaces. In anotherembodiment Station Interface instructions may be received from theStation. In yet another embodiment Station Interface instructions may bereceived via a dedicated media connected device of arbitrary complexityconnected to Station Interfaces.

Stations 101 may be of any arbitrary complexity as represented by, butnot limited to: U.S. Pat. No. 6,983,075 to Schwartz, et al., January2006; U.S. Pat. No. 6,973,513 to Chhabra, et al., December 2005; U.S.Pat. No. 5,742,608 to Randrianaliminana, et al., April 1998; U.S.Published Application US2005/0243857A1 by Hofstaedter, et al., November2005; U.S. Published Application US2005/0190701A1 by Benjerano, et al.,September 2005; U.S. Published Application US2005/0190731A1 byBenjerano, et al., September 2005; U.S. Published ApplicationUS2005/0135406A1 by Fleming, June 2005; U.S. Published ApplicationUS2004/0252716A1 by Memazie, December 2004; U.S. Published ApplicationUS2004/0076173A1 by Marchetto, April 2004; U.S. Published ApplicationUS2004/0001503A1 by Manter, January 2004; U.S. Published ApplicationUS2002/0126693A1 by Stark, et al., September 2002; and U.S. PublishedApplication US2002/0097741A1 by Tonella, July 2002; all of which arehereby incorporated herein by reference.

BSTTS messages 300 may be formed by adding to the standard messagepacket used by many system embodiments and known to one skilled in theart, such as, but not limited to, the fundamental frame layout usedhistorically and commonly in networking, for example, but not limited toFIG. 13 of U.S. Published Application US2002/0101874A1 by Whittaker, etal., August 2002; and U.S. Published Application US2002/0126691A1 byStrong, September 2002; all of which are hereby incorporated herein byreference.

Lengthy strings of all 1 or all 0 values may allow the StationInterfaces phase-locked loops detecting data frequency and/or phase todrift. Correcting for this drift can take time and can limit thebandwidth and throughput. Information delivery in many networkenvironments is improved if every byte of data is actually encoded withadditional control bit(s) to eliminate lengthy strings of all 1 or all 0values as described, for example, but not limited to, U.S. Pat. No.4,486,739 to Franaszek et al., incorporated herein by reference. Suchencodings are also used to enhance error correction at the byte level.

The various embodiments and approaches described above may be used invarious combinations. While specific examples of systems, procedures andoperations have been shown, based upon a reading thereof variations andmodifications of the embodiments disclosed herein will become apparentto one of skill in the art. Thus, the scope of the present inventionshould be determined by the appended claims and their legal equivalentswithout being limited by exemplary embodiments disclosed herein.

APPENDIX A Discussion of the Prior Art The Prior Art Discussed Below isHereby Incorporated by Reference Herein, as if Completely Set Forth inthe Specification.

U.S. Pat. No. 6,956,814 to Campanella, U.S. Pat. No. 6,922,388 toLaroja, et al., U.S. Pat. No. 4,731,880 to Ault Ct al., U.S. Pat. No.5,434,861 to Pritty et al., U.S. Pat. No. 5,517,622 to Ivanoff, et al.,U.S. Pat. No. 5,732,086 to Liang et al., U.S. Published PatentApplication U2005/0243857A1 by Hofstaedter, et al., U.S. PublishedPatent Application U2005/0047429A1 by Koo, et al., U.S. Published PatentApplication U2004/0013128A1 by Moreton, et al., U.S. Published PatentApplication U2003/0128665A1 by Bernhard, et al., U.S. Published PatentApplication U200210044565A1 by Park, et al., and U.S. Published PatentApplication US 2001/0033579A1 by Nelson, Jr., et al. describe networkimplementations that force-fit users transmitted messages onto thetransmission media using such techniques as Time Division Multiplexing(TDM) and Time Division Multiple Access (TDMA), Frequency DivisionMultiplexing (FDM) and Frequency Division Multiple Access (FDMA), acombination of FDM/TDM and FDMA/TDMA or TDM/FDM and TDMA/FDMA, or CodeDivision Multiplexing (CDM) and Code Division Multiple Access (CDMA), orOrthogonal Frequency Division Multiplexing (OFDM) and OrthogonalFrequency Division Multiple Access (OFDMA), at the expense of optimumbandwidth utilization and network complexity in contrast to most users'needs for increasing network speed and network simplification.

Ethernet Protocol

Networking standards, such as, but not limited to, IEEE 802.3 Ethernet,U.S. Pat. No. 6,751,231 to Fellman, et al., U.S. Pat. No. 6704302 toEinbinder, et al., U.S. Pat. No. 6,633,572 to Olshansky, et al., U.S.Pat. No. to 6,370,115 Smith, U.S. Pat. No. 6,320,870 to Thaler, U.S.Pat. No. 6,029,202 to Frazier et al., U.S. Pat. No. 5,995,549 to Crane,U.S. Pat. No. 5,850,525 to Kalkunte, et al., U.S. Pat. No. 5,838,688 toKadambi, et al., U.S. Pat. No. 5,568,476 to Sherer, et al., and U.S.Published Patent Application U2004/0223503A1 by Lynch show theshortcomings of Ethernet but fail to deliver adequate performance in theface of the increasing network speed and complexity. Nevertheless, dueto the inherent user community familiarity with, and low cost ofmass-produced components for, Ethernet is one of the most common networkprotocols. The primary problem with the Ethernet networks is thedependence on Carrier Sense Multiple Access/Collision Detection(CSMAICD) to establish the right of a station to transmit on a sharedmedium by detecting and/or avoiding message collisions. It has beenshown that this method allows no more than 30% of the availablebandwidth on a communications medium to be utilized. In attempts torecover this lost bandwidth, current high-speed networks have abandonedCSMA/CD in favor of point-to-point connections between layers of hubs,routers, and switches. This architecture merely moves the performanceproblem from that of bandwidth utilization to that of network latency asthe accumulation of switch after switch builds up delay between thesender of a message and its recipient.

Token Ring Protocol

Perhaps the earliest typical attempt to form an efficient network is byusing a token ring network, such as described in U.S. Pat. No. 6,449,283to Chao, et al., U.S. Pat. No. 5,890,001 to Hall, U.S. Pat. No.5,517,622 to Ivanoff, et al., U.S. Pat. No. 5,402,422 to Liu, et al.,U.S. Pat. No. 5,400,323 to Frenzell, III, et al., U.S. Pat. No.5,377,187 to Spiotta, et al., U.S. Pat. No. 5,245,605 to Ofek, U.S. Pat.No. 4,926,419 to Whipple, and U.S. Published Patent ApplicationUS2004/0223503A1 by Lynch. Token rings inefficiently and expensivelyimplement message transmission by passing a token message around a ringof stations. This ring of stations might actually be point-to-pointconnections between stations that have no ability to reconfigure withoutmajor manual rewiring efforts. More frequently, it is implemented in astar configuration where each station is wired to a central hub andjumper wires establish the transmission order. This configurationenables some degree of reconfiguration by manually moving jumper wires.Nevertheless, in either physical configuration, stations are pennittedto transmit when the token arrives empty at their input port. If thetoken is not empty when it arrives, then the message it contains ispassed on around the ring until the sending station resets its contentsflag.

The token ring approaches are limiting in a number of respects. Datatransmission is unidirectional around the ring, not multi-directional,thereby increasing the average latency before the receiving station seesthe message. Multidirectional transmission may be achieved through theadded expense and added complexity of multiple paths around the ring.Each station must ingest the incoming token, process it and then createa new message that is either a copy of the received token or a new tokenwith a new payload. This introduces further and significant latency tothe round trip time. The time to process the token also limits themaximum attainable throughput. Adding or deleting stations from such aring is a manual process, thereby prohibiting any notion of dynamicmembership in the network.

Clocked Network Protocol

Previously, clocked networks, such as described in U.S. Pat. No.5,434,861 to Pritty et al. focused on providing deterministiccommunications on a shared data bus among a small fixed number ofstations. The key to understanding that implementation is the concept ofa “network diameter.” This is the time it takes for a signal topropagate from a source at one extreme of the network to a receiver atthe furthest extreme of the network, and then back to the source. Thiscommunications environment is a predetermined, small number of nodes infixed configurations on electrical data buses that may be bidirectionalor unidirectional and connected in static configurations that are inlinear, branched or star form. Like its Ethernet predecessor, alimitation is that only one station is allowed to transmit within thetime span of a network diameter. Deterministic behavior is establishedby requiring that a unique fixed delay time be established for each nodeat system initialization. The values of these delays are in wholemultiples of the network diameter, thereby permitting only one node theauthority to transmit in one network diameter. If a station is not readyto transmit when its time arrives, then the network diameter delayallocated to that station remains unused, thereby wasting the bandwidthand limiting the network throughput. While Pritty discloses allowingstations to leave and later rejoin the network, no unexpected arrivalsare permitted, because the total membership is defined at systeminitialization. A polling master node sends a signal on the bus thatoffers to each station the opportunity to transmit after its built-indelay. A standby polling master will assume the duties of managing thedata flow if the first polling master fails.

Pritty describes an elegant and limited solution to a very narrowproblem domain, but the solution lacks the flexibility or efficiency toprovide well-organized, Self-Managed-Efficient ad hoc networking becauseeach node is going to consume one network diameter of bandwidth, thereis no ability to add stations that are not included at systeminitialization, a second failure of the polling node prevents the systemfrom operating and, even with a small number of stations, a systemadministrator is required to establish a unique time delay value foreach node.

Master-Slave Protocols

A number of master-slave networks have been developed over the years forspecific applications, such as, but not limited to, MIL-STD-1553, IEEE1394 (FireWire), Round Robin, Self-Aware networks, and Fiber Optic BusWavelength Division Multiplexing protocol.

MIL-STD-1553 uses a master controller to implement a predeterminedmessage schedule by commanding each station on the bus to transmit atthe appropriate time. Although slow by today's standards, this protocoldoes ensure that data are delivered at exactly the right time. It is,however, completely inflexible with respect to addition of stations, isconfined to specific transformer-coupled electrical devices, and permitsonly 31 nodes to be connected to any one bus.

IEEE 1394 (FireWire) is a commercial standard implementation that allowshigh-speed devices to communicate synchronously using clocked frames ata nominal 8 kHz, as discussed in U.S. Pat. No. 7,023,874 to Hauck, etal., U.S. Pat. No. 6,970,481 to Gray III, et al., U.S. Pat. No.6,947,442 to Saito, et al., U.S. Pat. No. 6,904,044to Duckwall, et al.,U.S. Pat. No. 6,771,668 to Fukunaga, et al., U.S. Pat. No. 6,765,923 toLaFollette, et al., U.S. Pat. Nos. 6,721,330 and 6,711,173 to Duckwall,et al., U.S. Pat. No. 6,643,723 to Heighway, et al., U.S. Pat. No.6,636,526 to Nyu, U.S. Pat. No. 6,496,485 to Le, U.S. Pat. No. 6,480,869to Saito, et al., U.S. Pat. No. 6,463,472 to Van Loo, U.S. Pat. No.6,457,081 to Gulick, U.S. Pat. No. 6,389,501 to Gamey, et al., U.S. Pat.No. 6,366,968 to Hunsaker, U.S. Pat. No. 6,298,406to Smyers, U.S. Pat.No. 6,295,516 to Takeyasu., U.S. Pat. No. 6,233,615 to Van Loo, U.S.Pat. No. 6,161,101 to Stakutis, et al., U.S. Pat. No. 6,065,052 to VanLoo, U.S. Pat. No. 5,802,057 to Duckwall, et al., U.S. Pat. No.5,802,048 to Duckwall, and U.S. Published Patent ApplicationUS2002/0085581A1 by Hauck, et al., U.S. Published Patent ApplicationUS2002/0093977A1 by Ono, et al.

The devices, each of which has a unique identification (ID) code, areorganized on the bus in a tree topology. One of the nodes is electedroot node and always has the highest ID. The IDs are assigned during theself-id process that happens after each bus-reset. Each device mustrequest from the controller the right to use one of two “isochronous”channels (where transmission is permitted every frame) or to makeasynchronous use of the remaining bandwidth in each data frame. Theisochronous channels cannot guarantee delivery of the data, the maximummessage size is a function of the cable speed, and any data exchange hasto run at the speed of the slowest device involved. While IEEE 1394 isan excellent mechanism for connecting high-speed peripherals to acentral processor, it does not meet the requirements of ad hocnetworking. It is confined to specific electrical connections, permits alimited number of devices, and has limits on the range between any pairof devices and the message size.

“Round Robin” global bus system have been implemented, such as thosedescribed in U.S. Pat. No. 6,975,324 to Valmiki, et al., U.S. Pat. No.6,975,324 to Patel, et al., U.S. Published Patent ApplicationUS2004/OO01 502A1 by Garmire, et al., U.S. Published Patent ApplicationUS2003/0108060A1 by Black, et al., U.S. Published Patent ApplicationUS2003/0108061A1 by Black, et al., U.S. Published Patent ApplicationUS2003/0043840A1 by Kurokawa, et al., and U.S. Published PatentApplication US2002/0044565A1 by Park, et al. In the embodiment describedby Park, a bus master (parent) polls the slaves (children) for theirstatus and assigns to each a time slot using TDM methodology. While thisimplementation can provide timely delivery of data, it is still confinedto the world of electrical control signals, and TDM essentially wastesthe bandwidth allocated to idle transmitters.

Existing Self-Aware Networks

Self-aware networks such as, but not limited to U.S. Pat. No. 5,732,086to Liang et al. attempt to provide message transmission functionality inan ad hoc environment. The system needs one node to be appointed as an“originating node” with the responsibility of determining andmaintaining the network topology. The environment in which it operatesmust permit full duplex transmission links between all nodes. Theoriginating node initially polls all stations, determines by theiracknowledgement their topology entry, and initiates normal operation. An“event” might cause that originating node to perform topology repairs byrepeating portions of the polling operation. Other nodes on the networkremain unaffected if their status in the topology has not changed. Whileattempting to approach dynamic network topology management, thisapproach, and others of its kind, fall short because all the nodes arewired with two-way links, thereby preventing the inclusion of unexpectednodes. Event detection is accomplished by nodes communicating a changeof state to one of the active nodes, and when an event is detected, allcommunications stop until the topology is re-established. While this maybe satisfactory fine for a very small number of stations and smallnetwork diameters, the bandwidth cost of these interruptions becomesprohibitive in a dynamic environment with a large number of stations.

Fiber Optic Bus Wavelength Division Multiplexing Protocol

U.S. Published Patent Application US2002/0101874A1 by Whittaker et al.attempts to overcome the limitations of TDM, FDM and combinations of TDMand FDM implementations for a plurality of stations on a real-time adhoc network. It combines the best characteristics of the Token Ring,Clocked, Master-Slave and Self-Aware network topologies, and is designedfor use on a linear optical data bus into which all nodes are tappedrather than point-to-point links. Separate, unrelated implementationssuch as disclosed in U.S. Pat. No. 5,898,801 to Braun et al., and U.S.Published Patent Application US2004/0076434A1 by Whittaker et al. allowthis tapping to occur without loss of signal energy on the bus at theexpense of diminished Signal to Noise ratio. While designed to operateon a linear bus, those implementations can be extended to work (with asignificant loss of effective bandwidth) on either a branching bus or ina broadcast medium.

Whittaker allows all stations the opportunity to transmit within thespace of one network diameter, thereby greatly improving the bandwidthutilization. Referring to the transition of the authority to transmitfrom one end of the transmission order to the other as one cycle, at thebeginning of a cycle, before any data are transmitted, a node designatedas the Starting Bus Master (SBM) sends out a Beginning of Sequence (BOS)message that resets all the active nodes on the bus. At the end of thecycle, the last node on the transmission order, the Ending Bus Master(EBM), sends out an End of Sequence (EOS) message after its datamessage. Between these two messages, every active node has had theopportunity to send a message. If it had none to send, a node sends asynchronization message to transfer the transmit authority to itssuccessor on the transmission order.

Whittaker dynamically computes the transmission order by the SBM, whichis enabled by the presence of the EOS message. When the SBM sees the EGSmessage, instead of starting the next cycle immediately, it pauses forone network diameter to allow a joining station to identify itself. Sucha joining station would see the EOS message and immediately transmit arequest to join the network. When such a request is granted, datatransmission is suspended in a manner similar to that of the self-awarenetwork. A joining SBM is assigned by the joining station to be the nodefurthest from that joining station. The assigned SBM then measures itsdistance from all the other nodes including the joining station bypinging each station of interest, receiving a response, and recordingthe round-trip time accomplish each of these distance measurements. Theassigned SBM then forms the new transmission order by sorting the nodesby distance and begins a fresh data cycle.

While Whittaker discloses an improved approach to providing networkcapability for ad hoc networks, Whittaker also has a number oflimitations to providing optimum throughput, such as: in anyMaster/Slave embodiment, the use of a SBM and an EBM to maintain systemoperation causes serious concerns for system integrity and reliabilityin the face of the failure of either master node; by using BOS and EOSmessages and pausing every cycle for a network diameter, a significantportion of the bandwidth remains lost; when a new station joins thenetwork, as the number of nodes increases, the amount of time consumedby the process of interrogating all the nodes (twice) becomesprohibitive, thereby preventing the system from guaranteeing timelydelivery of data in an ad hoc environment; and the algorithm fordetermining the transmission order only develops efficient sequences ona linear bus without branches. In a branched networks or free spacenetworks, this algorithm tends to develop exactly the wrong sequence ofnodes because it orders their transmission by their distance from themaster node.

Collision Avoidance, Detection, and Management

U.S. Pat. No. 7,012,927 to Nichols, U.S. Pat. No. 7,009,993 to Pronk,U.S. Pat. No. 7,006,521 to Nguyen, U.S. Pat. No. 7,006,469 to Roark,U.S. Pat. No. 7,002,984 to Cheng, U.S. Pat. No. 6,993,042 to Akatsuka,U.S. Pat. No. 6,990,072 to Alasti, U.S. Pat. No. 6,980,562 to Rudolf,U.S. Pat. No. 6,980,561 to Abi-Nassif, U.S. Pat. No. 6,977,919 toStanwood, U.S. Published Patent Application US200610056440A1 byKhartabil, U.S. Published Patent Application US2006/0039400A1 byMukhopadhyay, U.S. Published Patent Application US2006/0039342A1 byFrank, U.S. Published Patent Application US2005/0276276A1 by Davis, andU.S. Published Patent Application US2005/0243858A1 by Vitebsky; all ofwhich are hereby incorporated herein by reference, disclose collisiondetection, and/or collision management, and/or arbitration, and/orcontention processing logic. However, these inventions may not operateas well in an environment where stations are joining and dropping out.

1. A method for operating a network, the network comprising a pluralityof stations, each station being capable of transmitting and receiving,the method comprising: (a) defining an Authorization To TransmitSequence (ATTS) which specifies the order in which the stations maytransmit, the ATTS listing a first station, at least one intermediatestation, and a last station; (b) transmitting a message from the firststation; (c) transmitting a message from each of the intermediatestations in their order of listing; (d) transmitting a message from thelast station; (e) reversing the order of the ATTS; (f) transmittinganother message from the last station; (g) transmitting another messagefrom each of the intermediate stations in their reverse order oflisting; (h) transmitting another message from the first station; and(i) returning to step (b).
 2. The method of claim 1 wherein step (e)comprises defining a reverse ATTS which specifies the order in which thestations may transmit and which order is reverse to that of the ATTSdefined in step (a).
 3. A method of operating a station in a networkcomprising a plurality of stations, each station being capable oftransmitting and receiving, the method comprising: (a) obtaining anAuthorization To Transmit Sequence (ATTS) which specifies the order inwhich the stations may transmit, the ATTS listing a first station, atleast one intermediate station, and a last station; (b) defining areverse ATTS based upon the ATTS, the order in which the stations maytransmit being reverse to the order of the ATTS defined in step (a); (c)receiving messages; (d) inspecting each message to determine if it wasfrom a predecessor station in the ATTS or in the reverse ATTS; and (e)if the message was from a predecessor station then, once that message iscomplete, transmitting a message.
 4. The method of claim 3 and furthercomprising: estimating the time at which a message from the predecessorstation should be received; if that estimated time has passed and amessage has not been received from the predecessor station thentransmitting a message.
 5. The method of claim 3 and further comprising:estimating the time at which a message from the predecessor stationshould be received; if that estimated time has passed and a message hasnot been received from the predecessor station then removing thatpredecessor station from the ATTS and the reverse ATTS.
 6. The method ofclaim 3 and further comprising: estimating the time at which a messagefrom the predecessor station should be received; if that estimated timehas passed and a message has not been received from the predecessorstation then transmitting a message and removing that predecessorstation from the ATTS and the reverse ATTS.
 7. A method of operating astation in a network comprising a plurality of stations, each stationbeing capable of transmitting and receiving, the method comprising: (a)obtaining an Authorization To Transmit Sequence (ATTS) which specifiesthe order in which the stations may transmit, the ATTS listing a firststation, at least one intermediate station, and a last station; (b) at apredetermined time, sending a pause message to invite a new station tojoin the network; (c) if a reply message is received then sending astation identity and the ATTS to the new station; (d) receiving arevised ATTS from the new station, the revised ATTS listing the newstation; and (e) transmitting a message in accordance with the revisedATTS.
 8. The method of claim 7 wherein step (e) comprises: inspectingeach message to determine if it was from a predecessor station in therevised ATTS; and (e) if the message was from a predecessor stationthen, once that message is complete, beginning transmission of amessage.
 9. A method of operating a joining station, the station wishingto join a network comprising a plurality of stations, each station beingcapable of transmitting and receiving, the method comprising: (a)listening on the network for a pause message inviting new stations tojoin the network; (b) sending a reply to the pause message; (c)receiving an Authorization To Transmit Sequence (ATTS) which specifiesthe order in which the stations may transmit, the ATTS listing a firststation, at least one intermediate station, and a last station; (d)determining propagation times between the joining station and at leastsome of the stations listed in the ATTS; (e) determining a position inthe ATTS where the joining station should be placed; (f) defining arevised ATTS listing the joining station in that position; (g) receivinga message authorizing the joining station to transmit; (h) transmittinga message, the message including the revised ATTS; and (i) transmittingfurther messages in accordance with the revised ATTS.
 10. The method ofclaim 9 wherein step (e) comprises determining the position so as tomaintain network efficiency.
 11. A method of operating a joiningstation, the station wishing to join a network comprising a plurality ofstations, each station being capable of transmitting and receiving, themethod comprising: (a) listening on the network for a pause messageinviting new stations to join the network; (b) sending a reply to thepause message; (c) receiving a designation of a Parent Station in acluster and at least part of an Authorization To Transmit Sequence(ATTS) which specifies the order in which the stations may transmit, theATTS listing a first station, at least one intermediate station, and alast station, the at least part including stations in the cluster; (d)determining propagation times between the joining station and at leastsome of the stations in that cluster which are listed in the at leastpart of the ATTS; (e) determining a position in the at least part of theATTS where the joining station should be placed with respect to thestations in that cluster so as to maintain network efficiency; (f)defining a revised at least part of the ATTS listing the joining stationin that position; (g) receiving a message authorizing the joiningstation to transmit; (h) transmitting a message, the message includingthe revised at least part of the ATTS; and (i) transmitting furthermessages in accordance with the at least part of the revised ATTS. 12.The method of claim 11 wherein the step (c) of receiving at least partof an ATTS comprises receiving a local ATTS, the local ATTS beingincluded within the ATTS.
 13. The method of claim 11 wherein step (e)comprises: determining a plurality of network propagation times, eachnetwork propagation time being for a different ordering of transmissionsfor the at least part of the ATTS and including the joining station, andbeing based upon propagation times between the joining station and atleast some of the stations in that cluster which are listed in the atleast part of the ATTS; determining the minimum propagation time of theplurality of network propagation times; providing the ordering oftransmissions which resulted in the minimum propagation time as arevised at least part of the ATTS.
 14. A network, comprising: aplurality of stations, each station being capable of transmitting andreceiving, each station comprising: a transmitter to transmit messages;a receiver to receive messages; a controller functionally connected tothe transmitter to control the transmitter, functionally connected tothe receiver to process messages received by the receiver, and having amemory to store and retrieve an Authorization To Transmit Sequence(ATTS) which specifies an order in which the stations may transmit, theATTS listing a first station of the plurality of stations, at least oneintermediate station of the plurality of stations, and a last station ofthe plurality of stations, the controller being responsive to the ATTSand to a reverse ATTS; the controller of the first station causes thetransmitter of the first station to transmit a first message if the ATTSis in effect, and the controller inspects a received message and causesthe transmitter of the first station to transmit a second message if thereverse ATTS is in effect and the received message was transmitted by animmediately preceding station in the reverse ATTS; the controller ofeach intermediate station inspects a received message and causes thetransmitter of the intermediate station to transmit a message if theATTS is in effect and the received message was transmitted by animmediately preceding station in the ATTS, and causes the transmitter ofthe intermediate station to transmit a message if the reverse ATTS is ineffect and the received message was transmitted by an immediatelypreceding station in the reverse ATTS; and the controller of the laststation inspects a received message and causes the transmitter of thelast station to transmit a first message if the ATTS is in effect andthe received message was transmitted by an immediately preceding stationin the ATTS, and causes the transmitter of the last station to transmita second message if the reverse ATTS is in effect and the receivedmessage was transmitted by an immediately preceding station in thereverse ATTS; whereby a sequence of transmission of the stations is forthe first station listed in the ATTS to transmit, each intermediatestation to transmit in its order of listing in the ATTS, the laststation listed in the ATTS to transmit, the last station to transmitagain, each intermediate station to transmit in its order of listing inthe reverse ATTS, and the first station to transmit again; and wherebythe sequence of transmission is executed at least one more time.
 15. Thenetwork of claim 14 wherein a controller implements a reverse ATTS byreversing the order in the ATTS.
 16. The network of claim 14 wherein thecontroller also causes the transmitter to transmit a message if the ATTSis in effect and a message was not timely received from an immediatelypreceding station in the ATTS, or causes the transmitter to transmit amessage if the reverse ATTS is in effect and a message was timelyreceived from an immediately preceding station in the reverse ATTS. 17.The network of claim 14 wherein a station further comprises a stationinterface, and the controller is in the station interface.
 18. Astation, comprising: a transmitter to transmit messages; a receiver toreceive messages; and a controller functionally connected to thetransmitter to control the transmitter, functionally connected to thereceiver to process messages received by the receiver, and having amemory to store and retrieve an Authorization To Transmit Sequence(ATTS) which specifies when the station may transmit with respect toother stations listed in the ATTS, the ATTS listing a plurality ofstations, the plurality of stations having a first station, at least oneintermediate station, and a last station, the controller beingresponsive to the ATTS and to a reverse ATTS to cause the transmitter totransmit; the controller inspecting a received message and causing thetransmitter to transmit a message if the ATTS is in effect and thereceived message was transmitted by an immediately preceding station inthe ATTS, or causing the transmitter to transmit a message if thereverse ATTS is in effect and the received message was transmitted by animmediately preceding station in the reverse ATTS.
 19. The station ofclaim 18 wherein a controller implements a reverse ATTS by reversing theorder in the ATTS.
 20. The station of claim 18 wherein the controlleralso causes the transmitter to transmit a message if the ATTS is ineffect and a message was not timely received from an immediatelypreceding station in the ATTS, or causes the transmitter to transmit amessage if the reverse ATTS is in effect and a message was timelyreceived from an immediately preceding station in the reverse ATTS. 21.The station of claim 18 wherein the station is the first station in theATTS and the controller of the first station causes the transmitter ofthe first station to transmit a first message if the ATTS is in effect,and the controller inspects a received message and causes thetransmitter of the first station to transmit a second message if thereverse ATTS is in effect and the received message was transmitted by animmediately preceding station in the reverse ATTS.
 22. The station ofclaim 18 wherein the station is the last station in the ATTS and thecontroller of the last station inspects a received message and causesthe transmitter of the last station to transmit a first message if theATTS is in effect and the received message was transmitted by animmediately preceding station in the ATTS, and causes the transmitter ofthe last station to transmit a second message if the reverse ATTS is ineffect and the received message was transmitted by an immediatelypreceding station in the reverse ATTS.
 23. The network of claim 18wherein a station further comprises a station interface, and thecontroller is in the station interface.